Pelvis | Health Dictionary

The bony pelvis consists of the two hip bones, one on each side, with the sacrum and coccyx behind. It connects the lower limbs with the spine. In the female it is shallower than in the male and the ilia are more widely separated, giving great breadth to the hips of the woman; the inlet is more circular and the outlet larger; whilst the angle beneath the pubic bones (subpubic angle), which is an acute angle in the male, is obtuse in the female. All these points are of importance in connection with childbearing.

The contents of the pelvis are the urinary bladder and rectum in both sexes; in addition the male has the seminal vesicles and the prostate gland surrounding the neck of the bladder, whilst the female has the womb, ovaries, and their appendages.

A second meaning is as in renal pelvis – that part of the collecting system proximal to the URETER which collects urine from the renal pyramids (see KIDNEYS).

Pelvis | Health Dictionary

Keywords of this word: Pelvis

Medical Dictionary

The lower part of the trunk. Above, and separated from it by the diaphragm, lies the thorax or chest, and below lies the PELVIS, generally described as a separate cavity though continuous with that of the abdomen. Behind are the SPINAL COLUMN and lower ribs, which come within a few inches of the iliac bones. At the sides the contained organs are protected by the iliac bones and down-sloping ribs, but in front the whole extent is protected only by soft tissues. The latter consist of the skin, a varying amount of fat, three layers of broad, ?at muscle, another layer of fat, and ?nally the smooth, thin PERITONEUM which lines the whole cavity. These soft tissues allow the necessary distension when food is taken into the STOMACH, and the various important movements of the organs associated with digestion. The shape of the abdomen varies; in children it may protrude considerably, though if this is too marked it may indicate disease. In healthy young adults it should be either slightly prominent or slightly indrawn, and should show the outline of the muscular layer, especially of the pair of muscles running vertically (recti), which are divided into four or ?ve sections by transverse lines. In older people fat is usually deposited on and inside the abdomen. In pregnancy the abdomen enlarges from the 12th week after conception as the FETUS in the UTERUS grows (see PREGNANCY AND LABOUR; ANTENATAL CARE).

Contents The principal contents of the abdominal cavity are the digestive organs, i.e. the stomach and INTESTINE, and the associated glands, the LIVER and PANCREAS. The position

of the stomach is above and to the left when the individual is lying down, but may be much lower when standing. The liver lies above and to the right, largely under cover of the ribs, and occupying the hollow of the diaphragm. The two KIDNEYS lie against the back wall on either side, protected by the last two ribs. From the kidneys run the URETERS, or urinary ducts, down along the back wall to the URINARY BLADDER in the pelvis. The pancreas lies across the spine between the kidneys, and on the upper end of each kidney is a suprarenal gland

(see ADRENAL GLANDS). The SPLEEN is positioned high up on the left and partly behind the stomach. The great blood vessels and nerves lie on the back wall, and the remainder of the space is taken up by the intestines or bowels (see INTESTINE). The large intestine lies in the ?anks on either side in front of the kidneys, crossing below the stomach from right to left, while the small intestine hangs from the back wall in coils which ?ll up the spaces between the other organs. Hanging down from the stomach in front of the bowels is the OMENTUM, or apron, containing much fat and helping to protect the bowels. In pregnancy the UTERUS, or womb, rises up from the pelvis into the abdomen as it increases in size, lifting the coils of the small intestine above it.

The PELVIS is the part of the abdomen within the bony pelvis (see BONE), and contains the rectum or end part of the intestine, the bladder, and in the male the PROSTATE GLAND; in the female the uterus, OVARIES, and FALLOPIAN TUBES.... Medical Dictionary

Medical Dictionary

The cup-shaped socket on the pelvis in which rests the head of the femur or thigh-bone, the two forming the HIP-JOINT.... Medical Dictionary

Medical Dictionary

The large vessel which opens out of the left ventricle of the HEART and carries blood to all of the body. It is about 45 cm (1••• feet) long and 2·5 cm (1 inch) wide. Like other arteries it possesses three coats, of which the middle one is much the thickest. This consists partly of muscle ?bre, but is mainly composed of an elastic substance called elastin. The aorta passes ?rst to the right, and lies nearest the surface behind the end of the second right rib-cartilage; then it curves backwards and to the left, passes down behind the left lung close to the backbone, and through an opening in the diaphragm into the abdomen. There it divides, at the level of the navel, into the two common iliac arteries, which carry blood to the lower limbs.

Its branches, in order, are: two coronary arteries to the heart wall; the brachiocephalic, left common carotid, and left subclavian arteries to the head, neck and upper limbs; several small branches to the oesophagus, bronchi, and other organs of the chest; nine pairs of intercostal arteries which run around the body between the ribs; one pair of subcostal arteries which is in series with the intercostal arteries; four (or ?ve) lumbar arteries to the muscles of the loins; coeliac trunk to the stomach, liver and pancreas; two mesenteric arteries to the bowels; and suprarenal, renal and testicular arteries to the suprarenal body, kidney, and testicle on each side. From the termination of the aorta rises a small branch, the median sacral artery, which runs down into the pelvis. In the female the ovarian arteries replace the testicular.

The chief diseases of the aorta are ATHEROMA


Medical Dictionary

Arteries are vessels which convey oxygenated blood away from the heart to the tissues of the body, limbs and internal organs. In the case of most arteries the blood has been puri?ed by passing through the lungs, and is consequently bright red in colour; but in the pulmonary arteries, which convey the blood to the lungs, it is deoxygenated, dark, and like the blood in veins.

The arterial system begins at the left ventricle of the heart with the AORTA, which gives o? branches that subdivide into smaller and smaller vessels. The ?nal divisions, called arterioles, are microscopic and end in a network of capillaries which perforate the tissues like the pores of a sponge and bathe them in blood that is collected and brought back to the heart by veins. (See CIRCULATORY SYSTEM OF THE BLOOD.)

The chief arteries after the aorta and its branches are:

(1) the common carotid, running up each side of the neck and dividing into the internal carotid to the brain, and external carotid to the neck and face;

(2) the subclavian to each arm, continued by the axillary in the armpit, and the brachial along the inner side of the arm, dividing at the elbow into the radial and the ulnar,

which unite across the palm of the hand in arches that give branches to the ?ngers;

(3) the two common iliacs, in which the aorta ends, each of which divides into the internal iliac to the organs in the pelvis, and the external iliac to the lower limb, continued by the femoral in the thigh, and the popliteal behind the knee, dividing into the anterior and posterior tibial arteries to the front and back of the leg. The latter passes behind the inner ankle to the sole of the foot, where it forms arches similar to those in the hand, and supplies the foot and toes by plantar branches.

Structure The arteries are highly elastic, dilating at each heartbeat as blood is driven into them, and forcing it on by their resiliency (see PULSE). Every artery has three coats: (a) the outer or adventitia, consisting of ordinary strong ?brous tissue; (b) the middle or media, consisting of muscular ?bres supported by elastic ?bres, which in some of the larger arteries form distinct membranes; and (c) the inner or intima, consisting of a layer of yellow elastic tissue on whose inner surface rests a layer of smooth plate-like endothelial cells, over which ?ows the blood. In the larger arteries the muscle of the middle coat is largely replaced by elastic ?bres, which render the artery still more expansile and elastic. When an artery is cut across, the muscular coat instantly shrinks, drawing the cut end within the ?brous sheath that surrounds the artery, and bunching it up, so that a very small hole is left to be closed by blood-clot. (See HAEMORRHAGE.)... Medical Dictionary

Medical Dictionary

Most people su?er from backache at times during their lives, much of which has no identi?able cause – non-speci?c back pain. This diagnosis is one of the biggest single causes of sickness absence in the UK’s working population. Certain occupations, such as those involving long periods of sedentary work, lifting, bending and awkward physical work, are especially likely to cause backache. Back pain is commonly the result of sporting activities.

Non-speci?c back pain is probably the result of mechanical disorders in the muscles, ligaments and joints of the back: torn muscles, sprained LIGAMENTS, and FIBROSITIS. These disorders are not always easy to diagnose, but mild muscular and ligamentous injuries are usually relieved with symptomatic treatment – warmth, gentle massage, analgesics, etc. Sometimes back pain is caused or worsened by muscle spasms, which may call for the use of antispasmodic drugs. STRESS and DEPRESSION (see MENTAL ILLNESS) can sometimes result in chronic backache and should be considered if no clear physical diagnosis can be made.

If back pain is severe and/or recurrent, possibly radiating around to the abdomen or down the back of a leg (sciatica – see below), or is accompanied by weakness or loss of feeling in the leg(s), it may be caused by a prolapsed intervertebral disc (slipped disc) pressing on a nerve. The patient needs prompt investigation, including MRI. Resting on a ?rm bed or board can relieve the symptoms, but the patient may need a surgical operation to remove the disc and relieve pressure on the a?ected nerve.

The nucleus pulposus – the soft centre of the intervertebral disc – is at risk of prolapse under the age of 40 through an acquired defect in the ?brous cartilage ring surrounding it. Over 40 this nucleus is ?rmer and ‘slipped disc’ is less likely to occur. Once prolapse has taken place, however, that segment of the back is never quite the same again, as OSTEOARTHRITIS develops in the adjacent facet joints. Sti?ness and pain may develop, sometimes many years later. There may be accompanying pain in the legs: SCIATICA is pain in the line of the sciatic nerve, while its rarer analogue at the front of the leg is cruralgia, following the femoral nerve. Leg pain of this sort may not be true nerve pain but referred from arthritis in the spinal facet joints. Only about 5 per cent of patients with back pain have true sciatica, and spinal surgery is most successful (about 85 per cent) in this group.

When the complaint is of pain alone, surgery is much less successful. Manipulation by physiotherapists, doctors, osteopaths or chiropractors can relieve symptoms; it is important ?rst to make sure that there is not a serious disorder such as a fracture or cancer.

Other local causes of back pain are osteoarthritis of the vertebral joints, ankylosing spondylitis (an in?ammatory condition which can severely deform the spine), cancer (usually secondary cancer deposits spreading from a primary tumour elsewhere), osteomyelitis, osteoporosis, and PAGET’S DISEASE OF BONE. Fractures of the spine – compressed fracture of a vertebra or a break in one of its spinous processes – are painful and potentially dangerous. (See BONE, DISORDERS OF.)

Backache can also be caused by disease elsewhere, such as infection of the kidney or gall-bladder (see LIVER), in?ammation of the PANCREAS, disorders in the UTERUS and PELVIS or osteoarthritis of the HIP. Treatment is e?ected by tackling the underlying cause. Among the many known causes of back pain are:

Mechanical and traumatic causes

Congenital anomalies. Fractures of the spine. Muscular tenderness and ligament strain. Osteoarthritis. Prolapsed intervertebral disc. Spondylosis.

In?ammatory causes

Ankylosing spondylitis. Brucellosis. Osteomyelitis. Paravertebral abscess. Psoriatic arthropathy. Reiter’s syndrome. Spondyloarthropathy. Tuberculosis.

Neoplastic causes

Metastatic disease. Primary benign tumours. Primary malignant tumours.

Metabolic bone disease

Osteomalacia. Osteoporosis. Paget’s disease.

Referred pain

Carcinoma of the pancreas. Ovarian in?ammation and tumours. Pelvic disease. Posterior duodenal ulcer. Prolapse of the womb.

Psychogenic causes

Anxiety. Depression.

People with backache can obtain advice from Medical Dictionary

Medical Dictionary

Sacs formed of muscular and ?brous tissue and lined by a mucous membrane, which is united loosely to the muscular coat so as freely to allow increase and decrease in the contained cavity. Bladders are designed to contain some secretion or excretion, and communicate with the exterior by a narrow opening through which their contents can be discharged. In humans there are two: the gall-bladder and the urinary bladder.

Gall-bladder This is situated under the liver in the upper part of the abdomen, and its function is to store the BILE, which it discharges into the intestine by the BILE DUCT. For further details, see LIVER.

Urinary bladder This is situated in the pelvis, in front of the last part of the bowel. In the full state, the bladder rises up into the abdomen and holds about 570 ml (a pint) of urine. Two ?ne tubes, called the ureters, lead into the bladder, one from each kidney; and the urethra, a tube as wide as a lead pencil when distended, leads from it to the exterior – a distance of 4 cm (1••• inches) in the female and 20 cm (8 inches) in the male. The exit from the bladder to the urethra is kept closed by a muscular ring which is relaxed every time urine is passed.... Medical Dictionary

Medical Dictionary

The framework upon which the rest of the body is built up. The bones are generally called the skeleton, though this term also includes the cartilages which join the ribs to the breastbone, protect the larynx, etc.

Structure of bone Bone is composed partly of ?brous tissue, partly of bone matrix comprising phosphate and carbonate of lime, intimately mixed together. The bones of a child are about two-thirds ?brous tissue, whilst those of the aged contain one-third; the toughness of the former and the brittleness of the latter are therefore evident.

The shafts of the limb bones are composed of dense bone, the bone being a hard tube surrounded by a membrane (the periosteum) and enclosing a fatty substance (the BONE MARROW); and of cancellous bone, which forms the short bones and the ends of long bones, in which a ?ne lace-work of bone ?lls up the whole interior, enclosing marrow in its meshes. The marrow of the smaller bones is of great importance. It is red in colour, and in it red blood corpuscles are formed. Even the densest bone is tunnelled by ?ne canals (Haversian canals) in which run small blood vessels, nerves and lymphatics, for the maintenance and repair of the bone. Around these Haversian canals the bone is arranged in circular plates called lamellae, the lamellae being separated from one another by clefts, known as lacunae, in which single bone-cells are contained. Even the lamellae are pierced by ?ne tubes known as canaliculi lodging processes of these cells. Each lamella is composed of very ?ne interlacing ?bres.

GROWTH OF BONES Bones grow in thickness from the ?brous tissue and lime salts laid down by cells in their substance. The long bones grow in length from a plate of cartilage (epiphyseal cartilage) which runs across the bone about 1·5 cm or more from its ends, and which on one surface is also constantly forming bone until the bone ceases to lengthen at about the age of 16 or 18. Epiphyseal injury in children may lead to diminished growth of the limb.

REPAIR OF BONE is e?ected by cells of microscopic size, some called osteoblasts, elaborating the materials brought by the blood and laying down strands of ?brous tissue, between which bone earth is later deposited; while other cells, known as osteoclasts, dissolve and break up dead or damaged bone. When a fracture has occurred, and the broken ends have been brought into contact, these are surrounded by a mass of blood at ?rst; this is partly absorbed and partly organised by these cells, ?rst into ?brous tissue and later into bone. The mass surrounding the fractured ends is called the callus, and for some months it forms a distinct thickening which is gradually smoothed away, leaving the bone as before the fracture. If the ends have not been brought accurately into contact, a permanent thickening results.

VARIETIES OF BONES Apart from the structural varieties, bones fall into four classes: (a) long bones like those of the limbs; (b) short bones composed of cancellous tissue, like those of the wrist and the ankle; (c) ?at bones like those of the skull; (d) irregular bones like those of the face or the vertebrae of the spinal column (backbone).

The skeleton consists of more than 200 bones. It is divided into an axial part, comprising the skull, the vertebral column, the ribs with their cartilages, and the breastbone; and an appendicular portion comprising the four limbs. The hyoid bone in the neck, together with the cartilages protecting the larynx and windpipe, may be described as the visceral skeleton.

AXIAL SKELETON The skull consists of the cranium, which has eight bones, viz. occipital, two parietal, two temporal, one frontal, ethmoid, and sphenoid; and of the face, which has 14 bones, viz. two maxillae or upper jaw-bones, one mandible or lower jaw-bone, two malar or cheek bones, two nasal, two lacrimal, two turbinal, two palate bones, and one vomer bone. (For further details, see SKULL.) The vertebral column consists of seven vertebrae in the cervical or neck region, 12 dorsal vertebrae, ?ve vertebrae in the lumbar or loin region, the sacrum or sacral bone (a mass formed of ?ve vertebrae fused together and forming the back part of the pelvis, which is closed at the sides by the haunch-bones), and ?nally the coccyx (four small vertebrae representing the tail of lower animals). The vertebral column has four curves: the ?rst forwards in the neck, the second backwards in the dorsal region, the third forwards in the loins, and the lowest, involving the sacrum and coccyx, backwards. These are associated with the erect attitude, develop after a child learns to walk, and have the e?ect of diminishing jars and shocks before these reach internal organs. This is aided still further by discs of cartilage placed between each pair of vertebrae. Each vertebra has a solid part, the body in front, and behind this a ring of bone, the series of rings one above another forming a bony canal up which runs the spinal cord to pass through an opening in the skull at the upper end of the canal and there join the brain. (For further details, see SPINAL COLUMN.) The ribs – 12 in number, on each side – are attached behind to the 12 dorsal vertebrae, while in front they end a few inches away from the breastbone, but are continued forwards by cartilages. Of these the upper seven reach the breastbone, these ribs being called true ribs; the next three are joined each to the cartilage above it, while the last two have their ends free and are called ?oating ribs. The breastbone, or sternum, is shaped something like a short sword, about 15 cm (6 inches) long, and rather over 2·5 cm (1 inch) wide.

APPENDICULAR SKELETON The upper limb consists of the shoulder region and three segments – the upper arm, the forearm, and the wrist with the hand, separated from each other by joints. In the shoulder lie the clavicle or collar-bone (which is immediately beneath the skin, and forms a prominent object on the front of the neck), and the scapula or shoulder-blade behind the chest. In the upper arm is a single bone, the humerus. In the forearm are two bones, the radius and ulna; the radius, in the movements of alternately turning the hand palm up and back up (called supination and pronation respectively), rotating around the ulna, which remains ?xed. In the carpus or wrist are eight small bones: the scaphoid, lunate, triquetral, pisiform, trapezium, trapezoid, capitate and hamate. In the hand proper are ?ve bones called metacarpals, upon which are set the four ?ngers, each containing the three bones known as phalanges, and the thumb with two phalanges.

The lower limb consists similarly of the region of the hip-bone and three segments – the thigh, the leg and the foot. The hip-bone is a large ?at bone made up of three – the ilium, the ischium and the pubis – fused together, and forms the side of the pelvis or basin which encloses some of the abdominal organs. The thigh contains the femur, and the leg contains two bones – the tibia and ?bula. In the tarsus are seven bones: the talus (which forms part of the ankle joint); the calcaneus or heel-bone; the navicular; the lateral, intermediate and medial cuneiforms; and the cuboid. These bones are so shaped as to form a distinct arch in the foot both from before back and from side to side. Finally, as in the hand, there are ?ve metatarsals and 14 phalanges, of which the great toe has two, the other toes three each.

Besides these named bones there are others sometimes found in sinews, called sesamoid bones, while the numbers of the regular bones may be increased by extra ribs or diminished by the fusion together of two or more bones.... Medical Dictionary

Medical Dictionary

The operation used to deliver a baby through its mother’s abdominal wall. It is performed when the risks to mother or child of vaginal delivery are thought to outweigh the problems associated with operative delivery. One of the most common reasons for Caesarean section is ‘disproportion’ between the size of the fetal head and the maternal pelvis. The need for a Caesarean should be assessed anew in each pregnancy; a woman who has had a Caesarean section in the past will not automatically need to have one for subsequent deliveries. Caesarean-section rates vary dramatically from hospital to hospital, and especially between countries, emphasising that the criteria for operative delivery are not universally agreed. The current rate in the UK is about 23 per cent, and in the USA, about 28 per cent. The rate has shown a steady rise in all countries over the last decade. Fear of litigation by patients is one reason for this rise, as is the uncertainty that can arise from abnormalities seen on fetal monitoring during labour. Recent research suggesting that vaginal delivery is becoming more hazardous as the age of motherhood rises may increase the pressure from women to have a Caesarean section – as well as pressure from obstetricians.

The operation is usually performed through a low, horizontal ‘bikini line’ incision. A general anaesthetic in a heavily pregnant woman carries increased risks, so the operation is often performed under regional – epidural or spinal – ANAESTHESIA. This also allows the mother to see her baby as soon as it is born, and the baby is not exposed to agents used for general anaesthesia. If a general anaesthetic is needed (usually in an emergency), exposure to these agents may make the baby drowsy for some time afterwards.

Another problem with delivery by Caesarean section is, of course, that the mother must recover from the operation whilst coping with the demands of a small baby. (See PREGNANCY AND LABOUR.)... Medical Dictionary

Medical Dictionary

A two-pronged instrument with pointed ends, for the measurement of diameters, such as that of the pelvis in obstetrics.... Medical Dictionary

Medical Dictionary

Calyx means a cup-shaped cavity, the term being especially applied to the recesses of the pelvis of the kidney.... Medical Dictionary

Herbal Medical

A sac in the back of the pelvic region that drains the lymph from the intestinal tract, pelvis and legs, and acts as the beginning of the thoracic duct. See LACTEALS, THORACIC DUCT... Herbal Medical

Medical Dictionary

The lower end of the SPINAL COLUMN, resembling a bird’s beak and consisting of four fused nodules of bone; these represent vertebrae and correspond to the tail in lower animals. Above the coccyx lies a much larger bone, the SACRUM, and together they form the back wall of the PELVIS, which protects the organs in the lower ABDOMEN.... Medical Dictionary

Herbal Medical

A chronic in?ammatory bowel disease which has a protracted, relapsing and remitting course. An autoimmune condition, it may last for several years. There are many similarities with ULCERATIVE COLITIS; sometimes it can be hard to di?erentiate between the two conditions. A crucial di?erence is that ulcerative colitis is con?ned to the colon (see INTESTINE), whereas Crohn’s disease can a?ect any part of the gastrointestinal tract, including the mouth and anus. The sites most commonly a?ected in Crohn’s disease (in order of frequency) are terminal ILEUM and right side of colon, just the colon, just the ileum and ?nally the ileum and JEJUNUM. The whole wall of the a?ected bowel is oedamatous (see OEDEMA) and thickened, with deep ulcers a characteristic feature. Ulcers may even penetrate the bowel wall, with abscesses and ?stulas developing. Another unusual feature is the presence in the a?ected bowel lining of islands of normal tissue.

Crohn’s disease is rare in the developing world, but in the western world the incidence is increasing and is now 6–7 per 100,000 population. Around 80,000 people in the UK have the disorder with more than 4,000 new cases occurring annually. Commonly Crohn’s disease starts in young adults, but a second incidence surge occurs in people over 70 years of age. Both genetic and environmental factors are implicated in the disease – for example, if one identical twin develops the disease, the second twin stands a high chance of being a?ected; and 10 per cent of su?erers have a close relative with in?ammatory bowel disease. Among environmental factors are low-residue, high-re?ned-sugar diets, and smoking.

Symptoms and signs of Crohn’s disease depend on the site a?ected but include abdominal pain, diarrhoea (sometimes bloody), ANOREXIA, weight loss, lethargy, malaise, ANAEMIA, and sore tongue and lips. An abdominal mass may be present. Complications can be severe, including life-threatening in?ammation of the colon (which may cause TOXAEMIA), perforation of the colon and the development of ?stulae between the bowel and other organs in the abdomen or pelvis. If Crohn’s disease persists for a decade or more there is an increased risk of the victim developing colon cancer. Extensive investigations are usually necessary to diagnose the disease; these include blood tests, bacteriological studies, ENDOSCOPY and biopsy, and barium X-ray examinations.

Treatment As with ulcerative colitis, treatment is aimed primarily at controlling symptoms. Physicians, surgeons, radiologists and dietitians usually adopt a team approach, while counsellors and patient support groups are valuable adjuncts in a disease that is typically lifelong. Drug treatment is aimed at settling the acute phase and preventing relapses. CORTICOSTEROIDS, given locally to the a?ected gut or orally, are used initially and the e?ects must be carefully monitored. If steroids do not work, the immunosuppressant agent AZATHIOPRINE should be considered. Antidiarrhoeal drugs may occasionally be helpful but should not be taken during an acute phase. The anti-in?ammatory drug SULFASALAZINE can be bene?cial in mild colitis. A new generation of genetically engineered anti-in?ammatory drugs is now available, and these selective immunosuppressants may prove of value in the treatment of Crohn’s disease.

Diet is important and professional guidance is advisable. Some patients respond to milk- or wheat-free diets, but the best course for most patients is to eat a well-balanced diet, avoiding items that the su?erer knows from experience are poorly tolerated. Of those patients with extensive disease, as many as 80 per cent may require surgery to alleviate symptoms: a section of a?ected gut may be removed or, as a lifesaving measure, a bowel perforation dealt with.


Medical Dictionary

A FETUS with a double PELVIS.... Medical Dictionary

Medicinal Plants Glossary

Slow or painful birth of a child. This may occur because the baby is large and/or the mother’s pelvis is small or wrongly shaped for the baby to pass through easily. Abnormal presentation of the baby is another cause (see PREGNANCY AND LABOUR; BREECH PRESENTATION).... Medicinal Plants Glossary

Herbal Medical

The condition in which the endometrium (the cells lining the interior of the UTERUS) is found in other parts of the body. The most common site of such misplaced endometrium is the muscle of the uterus. The next most common site is the ovary (see OVARIES), followed by the PERITONEUM lining the PELVIS, but it also occurs anywhere in the bowel. The cause is not known. Endometriosis never occurs before puberty and seldom after the menopause. The main symptoms it produces are MENORRHAGIA, DYSPAREUNIA, painful MENSTRUATION and pelvic pain. Treatment is usually by removal of the a?ected area, but in some cases satisfactory results are obtained from the administration of a PROGESTOGEN such as NORETHISTERONE, norethynodrel and DANAZOL.... Herbal Medical

Medical Dictionary

down the TRACHEA into the lungs, usually in the course of administering anaesthetics (see under ANAESTHESIA).

Eustachian catheters are small catheters that are passed along the ?oor of the nose into the Eustachian tube in order to in?ate the ear.

Nasal catheters are tubes passed through the nose into the stomach to feed a patient who cannot swallow – so-called nasal feeding.

Rectal catheters are passed into the RECTUM in order to introduce ?uid into the rectum.

Suprapubic catheters are passed into the bladder through an incision in the lower abdominal wall just above the pubis, either to allow urine to drain away from the bladder, or to wash out an infected bladder.

Ureteric catheters are small catheters that are passed up the ureter into the pelvis of the kidney, usually to determine the state of the kidney, either by obtaining a sample of urine direct from the kidney or to inject a radio-opaque substance preliminary to X-raying the kidney. (See PYELOGRAPHY.)

Urethral catheters are catheters that are passed along the urethra into the bladder, either to draw o? urine or to wash out the bladder.

It is these last three types of catheters that are most extensively used.... Medical Dictionary

Medical Dictionary

Introduction of ?uid into the RECTUM via the

Percutaneous nephroscope used for examining the interior of the kidney. It is passed into the pelvis of the kidney through a track from the surface of the skin. (The track is made with a needle and guide wire.) Instruments can be passed through the nephroscope under direct vision to remove calculi.

ANUS. Enemas may be given to clear the intestine of faeces prior to intestinal surgery or to relieve severe constipation. They may also be used to give barium for diagnostic X-rays as well as drugs such as CORTICOSTEROIDS, used to treat ULCERATIVE COLITIS. The patient is placed on his or her side with a support under the hips. A catheter (see CATHETERS) with a lubricated end is inserted into the rectum and warmed enema ?uid gently injected. Disposable enemas and miniature enemas, which can be self-administered, are widely used; they contain preprepared solution.... Medical Dictionary

Medical Dictionary

The event during pregnancy when the presenting part of the baby, usually the head, moves down into the mother’s pelvis. (See PREGNANCY AND LABOUR.)... Medical Dictionary

Medical Dictionary

An uncommon but very malignant cancer of the bone in children and young adults, the condition was ?rst identi?ed as being di?erent from OSTEOSARCOMA by Dr J Ewing in 1921. It usually occurs in the limbs or pelvis and soon spreads to other parts of the body. Treatment is by RADIOTHERAPY and CYTOTOXIC drugs. Since the use of the latter, the number of patients who survive for ?ve years or more has much improved.... Medical Dictionary

Medical Dictionary

An escape of ?uid from the vessels or passages which ought to contain it. Extravasation of blood due to tearing of vessel walls is found in STROKE, and in the commoner condition known as a bruise. Extravasation of urine takes place when the bladder or the URETHRA is ruptured by a blow on the abdomen or on the crutch (PERINEUM), or torn in a fracture of the pelvis. Intravenous infusions frequently extravasate.... Medical Dictionary

Medical Dictionary

The thigh bone, which is the longest and strongest bone in the body. As the upper end is set at an angle of about 120 degrees to the rest of the bone, and since the weight of the body is entirely borne by the two femora, fracture of one of these bones close to its upper end is a common accident in old people, whose bones are often weakened by osteoporosis (see under BONE, DISORDERS OF). The femur ?ts, at its upper end, into the acetabulum of the pelvis, forming the hip-joint, and, at its lower end, meets the tibia and patella in the knee-joint.... Medical Dictionary

Medical Dictionary

An unnatural, narrow channel leading from some natural cavity – such as the duct of a gland, or the interior of the bowels – to the surface. Alternatively a ?stula may be a communication between two such cavities where none should exist – as, for example, a direct communication between the bladder and bowel.

Cause Fistulas may be congenital or develop as a result of injury or infection. A SALIVARY ?stula may develop between the salivary gland and the outside of the cheek because of a blockage in the duct from the gland to the mouth. A urinary ?stula may be one consequence of a fracture of the PELVIS which has damaged the URETHRA. Fistulas of the anus are one of the most common forms, usually the result of infection and ABSCESS formation.

Treatment As a rule, a ?stula is extremely di?cult to close, especially after it has persisted for some time. The treatment consists in an operation to restore the natural channel, be it salivary duct, or urethra, or bowel. This is e?ected by appropriate means in each locality, and when it is attained the ?stula heals quickly under simple dressings.... Medical Dictionary

Medical Dictionary

A species of gram-negative, rod-shaped BACTERIA. It occurs among the normal ?ora of the human mouth, COLON and reproductive tract. Occasionally, fusobacterium is isolated from abscesses occurring in the lungs, abdomen and pelvis. One variety occurs in patients with VINCENT’S ANGINA (trench mouth).... Medical Dictionary

Medical Dictionary

Blood in the URINE. The blood may come from any part of the urinary tract. When the blood comes from the kidney or upper part of the urinary tract, it is usually mixed throughout the urine, giving the latter a brownish or smoky tinge. This condition is usually the result of glomerulonephritis, or it may be present in persons su?ering from high blood pressure or PYELITIS. Blood may also appear in the urine when a stone or gravel is present in the pelvis of the kidney setting up irritation, especially after exercise. The blood may also originate from a bladder that is in?amed or infected or which contains benign growths (papilloma) or malignant growths. In?ammation or injury to the URETHRA can also cause haematuria. Someone with haematuria should seek medical advice. (See also KIDNEYS, DISEASES OF.)... Medical Dictionary

Medical Dictionary

That part of the body on each side of the pelvis where it articulates with the head of the femur (thigh bone).... Medical Dictionary

Medical Dictionary

The joint formed by the head of the thigh bone and the deep, cup-shaped hollow on the side of the pelvis which receives it (acetabulum). The joint is of the ball-and-socket variety, is dislocated only by very great violence, and is correspondingly di?cult to reduce to its natural state after dislocation. It is enclosed by a capsule of ?brous tissue, strengthened by several bands, of which the principal is the ilio-femoral or Y-shaped ligament placed in front of the joint. A round ligament also unites the head of the thigh bone to the margin of the acetabulum.

For hip-joint disease, see under JOINTS, DISEASES OF.... Medical Dictionary

Medical Dictionary

The uppermost of the three bones forming each side of the PELVIS. (See also BONE.)... Medical Dictionary

Medical Dictionary

This is diagnosed when a couple has not achieved a pregnancy after one year of regular unprotected sexual intercourse. Around 15–20 per cent of couples have di?culties in conceiving; in half of these cases the male partner is infertile, while the woman is infertile also in half; but in one-third of infertile couples both partners are a?ected. Couples should be investigated together as e?ciently and quickly as possible to decrease the distress which is invariably associated with the diagnosis of infertility. In about 10–15 per cent of women su?ering from infertility, ovulation is disturbed. Mostly they will have either irregular periods or no periods at all (see MENSTRUATION).

Checking a hormone pro?le in the woman’s blood will help in the diagnosis of ovulatory disorders like polycystic ovaries, an early menopause, anorexia or other endocrine illnesses. Ovulation itself is best assessed by ultrasound scan at mid-cycle or by a blood hormone progesterone level in the second half of the cycle.

The FALLOPIAN TUBES may be damaged or blocked in 20–30 per cent of infertile women. This is usually caused by previous pelvic infection or ENDOMETRIOSIS, where menstrual blood is thought to ?ow backwards through the fallopian tubes into the pelvis and seed with cells from the lining of the uterus in the pelvis. This process often leads to scarring of the pelvic tissues; 5–10 per cent of infertility is associated with endometriosis.

To assess the Fallopian tubes adequately a procedure called LAPAROSCOPY is performed. An ENDOSCOPE is inserted through the umbilicus and at the same time a dye is pushed through the tubes to assess their patency. The procedure is performed under a general anaesthetic.

In a few cases the mucus around the cervix may be hostile to the partner’s sperm and therefore prevent fertilisation.

Defective production is responsible for up to a quarter of infertility. It may result from the failure of the testes (see TESTICLE) to descend in early life, from infections of the testes or previous surgery for testicular torsion. The semen is analysed to assess the numbers of sperm and their motility and to check for abnormal forms.

In a few cases the genetic make-up of one partner does not allow the couple ever to achieve a pregnancy naturally.

In about 25 per cent of couples no obvious cause can be found for their infertility.

Treatment Ovulation may be induced with drugs.

In some cases damaged Fallopian tubes may be repaired by tubal surgery. If the tubes are destroyed beyond repair a pregnancy may be achieved with in vitro fertilisation (IVF) – see under ASSISTED CONCEPTION.

Endometriosis may be treated either with drugs or laser therapy, and pregnancy rates after both forms of treatment are between 40–50 per cent, depending on the severity of the disease.

Few options exist for treating male-factor infertility. These are arti?cial insemination by husband or donor and more recently in vitro fertilisation. Drug treatment and surgical repair of VARICOCELE have disappointing results.

Following investigations, between 30 and 40 per cent of infertile couples will achieve a pregnancy usually within two years.

Some infertile men cannot repair any errors in the DNA in their sperm, and it has been found that the same DNA repair problem occurs in malignant cells of some patients with cancer. It is possible that these men’s infertility might be nature’s way of stopping the propagation of genetic defects. With the assisted reproduction technique called intracytoplasmic sperm injection, some men with defective sperm can fertilise an ovum. If a man with such DNA defects fathers a child via this technique, that child could be sterile and might be at increased risk of developing cancer. (See ARTIFICIAL INSEMINATION; ASSISTED CONCEPTION.)... Medical Dictionary

Medical Dictionary

All the alimentary canal beyond below the stomach. In it, most DIGESTION is carried on, and through its walls all the food material is absorbed into the blood and lymph streams. The length of the intestine in humans is about 8·5–9 metres (28–30 feet), and it takes the form of one continuous tube suspended in loops in the abdominal cavity.

Divisions The intestine is divided into small intestine and large intestine. The former extends from the stomach onwards for 6·5 metres (22 feet) or thereabouts. The large intestine is the second part of the tube, and though shorter (about 1·8 metres [6 feet] long) is much wider than the small intestine. The latter is divided rather arbitrarily into three parts: the duodenum, consisting of the ?rst 25–30 cm (10–12 inches), into which the ducts of the liver and pancreas open; the jejunum, comprising the next 2·4–2·7 metres (8–9 feet); and ?nally the ileum, which at its lower end opens into the large intestine.

The large intestine begins in the lower part of the abdomen on the right side. The ?rst part is known as the caecum, and into this opens the appendix vermiformis. The appendix is a small tube, closed at one end and about the thickness of a pencil, anything from 2 to 20 cm (average 9 cm) in length, which has much the same structure as the rest of the intestine. (See APPENDICITIS.) The caecum continues into the colon. This is subdivided into: the ascending colon which ascends through the right ?ank to beneath the liver; the transverse colon which crosses the upper part of the abdomen to the left side; and the descending colon which bends downwards through the left ?ank into the pelvis where it becomes the sigmoid colon. The last part of the large intestine is known as the rectum, which passes straight down through the back part of the pelvis, to open to the exterior through the anus.

Structure The intestine, both small and large, consists of four coats, which vary slightly in structure and arrangement at di?erent points but are broadly the same throughout the entire length of the bowel. On the inner surface there is a mucous membrane; outside this is a loose submucous coat, in which blood vessels run; next comes a muscular coat in two layers; and ?nally a tough, thin peritoneal membrane. MUCOUS COAT The interior of the bowel is completely lined by a single layer of pillar-like cells placed side by side. The surface is increased by countless ridges with deep furrows thickly studded with short hair-like processes called villi. As blood and lymph vessels run up to the end of these villi, the digested food passing slowly down the intestine is brought into close relation with the blood circulation. Between the bases of the villi are little openings, each of which leads into a simple, tubular gland which produces a digestive ?uid. In the small and large intestines, many cells are devoted to the production of mucus for lubricating the passage of the food. A large number of minute masses, called lymph follicles, similar in structure to the tonsils are scattered over the inner surface of the intestine. The large intestine is bare both of ridges and of villi. SUBMUCOUS COAT Loose connective tissue which allows the mucous membrane to play freely over the muscular coat. The blood vessels and lymphatic vessels which absorb the food in the villi pour their contents into a network of large vessels lying in this coat. MUSCULAR COAT The muscle in the small intestine is arranged in two layers, in the outer of which all the ?bres run lengthwise with the bowel, whilst in the inner they pass circularly round it. PERITONEAL COAT This forms the outer covering for almost the whole intestine except parts of the duodenum and of the large intestine. It is a tough, ?brous membrane, covered upon its outer surface with a smooth layer of cells.... Medical Dictionary

Medical Dictionary

Ischium is the bone which forms the lower and hinder part of the pelvis. It bears the weight of the body in sitting.... Medical Dictionary

Medical Dictionary

The name applied to the part of the back between the lower ribs and the pelvis. (For pain in the loins, see BACKACHE; LUMBAGO.)... Medical Dictionary

Medical Dictionary

Each kidney comprises over a million of these microscopic units which regulate and control the formation of URINE. A tuft of capillaries invaginates the Bowmans capsule, which is the blind-ending tube (GLOMERULUS) of each nephron. Plasma is ?ltered out of blood and through the Bowmans capsule into the renal tubule. As the ?ltrate passes along the tubule, most of the water and electrolytes are reabsorbed. The composition is regulated with the retention or addition of certain molecules (e.g. urea, drugs, etc.). The tubules eventually empty the ?ltrate, which by now is urine, into the renal pelvis from where it ?ows down the ureters into the bladder. (See KIDNEYS.)... Medical Dictionary

Medical Dictionary

An endoscopic instrument for examining the inside of the kidney (see KIDNEYS). It is normally passed into the renal pelvis of the organ via a route from the surface of the skin. Instruments can be passed through the nephroscope under direct vision to remove CALCULI (stones) or break them up using ULTRASOUND.... Medical Dictionary

Medical Dictionary

The climax of sexual intercourse. In men this coincides with ejaculation of the semen when the muscles of the pelvis force the seminal ?uid from the prostate into the urethra and out through the urethral ori?ce. In women, orgasm is typi?ed by irregular contractions of the muscular walls of the vagina followed by relaxation. The sensation is more di?use in women than in men and tends to last longer with successive orgasms sometimes occurring.... Medical Dictionary

Medical Dictionary

Measurement of the internal dimensions of the PELVIS. The four diameters measured are: transverse, anterioposterior, and left and right oblique. These measurements help to establish whether a fetus can be delivered normally. If the outlet is abnormally small, the mother will have to be delivered by CAESAREAN SECTION.... Medical Dictionary

Medical Dictionary

Pregnancy The time when a woman carries a developing baby in her UTERUS. For the ?rst 12 weeks (the ?rst trimester) the baby is known as an EMBRYO, after which it is referred to as the FETUS.

Pregnancy lasts about 280 days and is calculated from the ?rst day of the last menstrual period – see MENSTRUATION. Pregnancy-testing kits rely on the presence of the hormone beta HUMAN CHORIONIC GONADOTROPHIN (b HCG) which is excreted in the woman’s urine as early as 30 days from the last menstrual period. The estimated date of delivery can be accurately estimated from the size of the developing fetus measured by ULTRASOUND (see also below) between seven and 24 weeks. ‘Term’ refers to the time that the baby is due; this can range from 38 weeks to 41 completed weeks.

Physical changes occur in early pregnancy – periods stop and the abdomen enlarges. The breasts swell, with the veins becoming prominent and the nipples darkening. About two in three women will have nausea with a few experiencing such severe vomiting as to require hospital admission for rehydration.

Antenatal care The aim of antenatal care is to ensure a safe outcome for both mother and child; it is provided by midwives (see MIDWIFE) and doctors. Formal antenatal care began in Edinburgh in the 1930s with the recognition that all aspects of pregnancy – normal and abnormal – warranted surveillance. Cooperation between general practitioners, midwives and obstetricians is now established, with pregnancies that are likely to progress normally being cared for in the community and only those needing special intervention being cared for in a hospital setting.

The initial visit (or booking) in the ?rst half of pregnancy will record the history of past events and the results of tests, with the aim of categorising the patients into normal or not. Screening tests including blood checks and ultrasound scans are a routine part of antenatal care. The ?rst ultrasound scan is done at about 11 weeks to date the pregnancy, with a further one done at 20 weeks – the anomaly scan – to assess the baby’s structure. Some obstetric units will check the growth of the baby with one further scan later in the pregnancy or, in the case of twin pregnancies (see below), many scans throughout. The routine blood tests include checks for ANAEMIA, DIABETES MELLITUS, sickle-cell disease and THALASSAEMIA, as well as for the blood group. Evidence of past infections is also looked for; tests for RUBELLA (German measles) and SYPHILIS are routine, whereas tests for human immunode?ciency virus (see AIDS/ HIV below) and HEPATITIS are being o?ered as optional, although there is compelling evidence that knowledge of the mother’s infection status is bene?cial to the baby.

Traditional antenatal care consists of regular appointments, initially every four weeks until 34 weeks, then fortnightly or weekly. At each visit the mother’s weight, urine and blood pressure are checked, and assessment of fetal growth and position is done by palpating the uterus. Around two-thirds of pregnancies and labours are normal: in the remainder, doctors and midwives need to increase the frequency of surveillance so as to prevent or deal with maternal and fetal problems.

Common complications of pregnancy

Some of the more common complications of pregnancy are listed below.

As well as early detection of medical complications, antenatal visits aim to be supportive and include emotional and educational care. Women with uncomplicated pregnancies are increasingly being managed by midwives and general practitioners in the community and only coming to the hospital doctors should they develop a problem. A small number will opt for a home delivery, but facilities for providing such a service are not always available in the UK.

Women requiring more intensive surveillance have their management targeted to the speci?c problems encountered. Cardiologists will see mothers-to-be with heart conditions, and those at risk of diabetes are cared for in designated clinics with specialist sta?. Those women needing more frequent surveillance than standard antenatal care can be looked after in maternity day centres. These typically include women with mildly raised blood pressure or those with small babies. Fetal medicine units have specialists who are highly skilled in ultrasound scanning and specialise in the diagnosis and management of abnormal babies still in the uterus. ECTOPIC PREGNANCY Chronic abdominal discomfort early in pregnancy may be caused by unruptured ectopic pregnancy, when, rarely, the fertilised OVUM starts developing in the Fallopian tube (see FALLOPIAN TUBES) instead of the uterus. The patient needs hospital treatment and LAPAROSCOPY. A ruptured ectopic pregnancy causes acute abdominal symptoms and collapse, and the woman will require urgent abdominal surgery. URINARY TRACT INFECTIONS These a?ect around 2 per cent of pregnant women and are detected by a laboratory test of a mid-stream specimen of urine. In pregnancy, symptoms of these infections do not necessarily resemble those experienced by non-pregnant women. As they can cause uterine irritability and possible premature labour (see below), it is important to ?nd and treat them appropriately. ANAEMIA is more prevalent in patients who are vegetarian or on a poor diet. Iron supplements are usually given to women who have low concentrations of HAEMOGLOBIN in their blood (less than 10.5 g/dl) or who are at risk of becoming low in iron, from bleeding, twin pregnancies and those with placenta previa (see below). ANTEPARTUM HAEMORRHAGE Early in pregnancy, vaginal bleedings may be due to a spontaneous or an incomplete therapeutic ABORTION. Bleeding from the genital tract between 24 completed weeks of pregnancy and the start of labour is called antepartum haemorrhage. The most common site is where the PLACENTA is attached to the wall of the uterus. If the placenta separates before delivery, bleeding occurs in the exposed ‘bed’. When the placenta is positioned in the upper part of the uterus it is called an abruption. PLACENTA PRAEVIA is sited in the lower part and blocks or partly blocks the cervix (neck of the womb); it can be identi?ed at about the 34th week. Ten per cent of episodes of antepartum bleeding are caused by placenta previa, and it may be associated with bleeding at delivery. This potentially serious complication is diagnosed by ultrasound scanning and may require a caesarean section (see below) at delivery. INCREASED BLOOD PRESSURE, associated with protein in the urine and swelling of the limbs, is part of a condition known as PRE-ECLAMPSIA. This occurs in the second half of pregnancy in about 1 in 10 women expecting their ?rst baby, and is mostly very mild and of no consequence to the pregnancy. However, some women can develop extremely high blood pressures which can adversely a?ect the fetus and cause epileptic-type seizures and bleeding disorders in the mother. This serious condition is called ECLAMPSIA. For this reason a pregnant woman with raised blood pressure or PROTEIN in her urine is carefully evaluated with blood tests, often in the maternity day assessment unit. The condition can be stopped by delivery of the baby, and this will be done if the mother’s or the fetus’s life is in danger. If the condition is milder, and the baby not mature enough for a safe delivery, then drugs can be used to control the blood pressure. MISCARRIAGE Also called spontaneous abortion, miscarriage is the loss of the fetus. There are several types:

threatened miscarriage is one in which some vaginal bleeding occurs, the uterus is enlarged, but the cervix remains closed and pregnancy usually proceeds.

inevitable miscarriage usually occurs before the 16th week and is typi?ed by extensive blood loss through an opened cervix and cramp-like abdominal pain; some products of conception are lost but the developing placental area (decidua) is retained and an operation may be necessary to clear the womb.

missed miscarriages, in which the embryo dies and is absorbed, but the decidua (placental area of uterine wall) remains and may cause abdominal discomfort and discharge of old blood.

THERAPEUTIC ABORTION is performed on more than 170,000 women annually in England and Wales. Sometimes the woman may not have arranged the procedure through the usual health-care channels, so that a doctor may see a patient with vaginal bleeding, abdominal discomfort or pain, and open cervix – symptoms which suggest that the decidua and a blood clot have been retained; these retained products will need to be removed by curettage.

Septic abortions are now much less common in Britain than before the Abortion Act (1967) permitted abortion in speci?ed circumstances. The cause is the passage of infective organisms from the vagina into the uterus, with Escherichia coli and Streptococcus faecalis the most common pathogenic agents. The woman has abdominal pain, heavy bleeding, usually fever and sometimes she is in shock. The cause is usually an incomplete abortion or one induced in unsterile circumstances. Antibiotics and curettage are the treatment. INTRAUTERINE GROWTH RETARDATION describes a slowing of the baby’s growth. This can be diagnosed by ultrasound scanning, although there is a considerable margin of error in estimates of fetal weight. Trends in growth are favoured over one-o? scan results alone. GESTATIONAL DIABETES is a condition that is more common in women who are overweight or have a family member with diabetes. If high concentrations of blood sugar are found, e?orts are made to correct it as the babies can become very fat (macrosomia), making delivery more di?cult. A low-sugar diet is usually enough to control the blood concentration of sugars; however some women need small doses of INSULIN to achieve control. FETAL ABNORMALITIES can be detected before birth using ultrasound. Some of these defects are obvious, such as the absence of kidneys, a condition incompatible with life outside the womb. These women can be o?ered a termination of their pregnancy. However, more commonly, the pattern of problems can only hint at an abnormality and closer examination is needed, particularly in the diagnosis of chromosomal deformities such as DOWN’S (DOWN) SYNDROME (trisomy 21 or presence of three 21 chromosomes instead of two).

Chromosomal abnormalities can be de?nitively diagnosed only by cell sampling such as amniocentesis (obtaining amniotic ?uid – see AMNION – from around the baby) done at 15 weeks onwards, and chorionic villus sampling (sampling a small part of the placenta) – another technique which can be done from 12 weeks onwards. Both have a small risk of miscarriage associated with them; consequently, they are con?ned to women at higher risk of having an abnormal fetus.

Biochemical markers present in the pregnant woman’s blood at di?erent stages of pregnancy may have undergone changes in those carrying an abnormal fetus. The ?rst such marker to be routinely used was a high concentration of alpha-fetol protein in babies with SPINA BIFIDA (defects in the covering of the spinal cord). Fuller research has identi?ed a range of diagnostic markers which are useful, and, in conjunction with other factors such as age, ethnic group and ultrasound ?ndings, can provide a predictive guide to the obstetrician – in consultation with the woman – as to whether or not to proceed to an invasive test. These tests include pregnancy-associated plasma protein assessed from a blood sample taken at 12 weeks and four blood tests at 15–22 weeks – alphafetol protein, beta human chorionic gonadotrophin, unconjugated oestriol and inhibin A. Ultrasound itself can reveal physical ?ndings in the fetus, which can be more common in certain abnormalities. Swelling in the neck region of an embryo in early pregnancy (increased nuchal thickness) has good predictive value on its own, although its accuracy is improved in combination with the biochemical markers. The e?ectiveness of prenatal diagnosis is rapidly evolving, the aim being to make the diagnosis as early in the pregnancy as possible to help the parents make more informed choices. MULTIPLE PREGNANCIES In the UK, one in 95 deliveries is of twins, while the prevalence of triplets is one in 10,000 and quadruplets around one in 500,000. Racial variations occur, with African women having a prevalence rate of one in 30 deliveries for twins and Japanese women a much lower rate than the UK ?gure. Multiple pregnancies occur more often in older women, and in the UK the prevalence of fertility treatments, many of these being given to older women, has raised the incidence. There is now an o?cial limit of three eggs being transferred to a woman undergoing ASSISTED CONCEPTION (gamete intrafallopian transfer, or GIFT).

Multiple pregnancies are now usually diagnosed as a result of routine ultrasound scans between 16 and 20 weeks of pregnancy. The increased size of the uterus results in the mother having more or worse pregnancy-related conditions such as nausea, abdominal discomfort, backache and varicose veins. Some congenital abnormalities in the fetus occur more frequently in twins: NEURAL TUBE defects, abnormalities of the heart and the incidence of TURNER’S SYNDROME and KLINEFELTER’S SYNDROME are examples. Such abnormalities may be detected by ultrasound scans or amniocentesis. High maternal blood pressure and anaemia are commoner in women with multiple pregnancies (see above).

The growth rates of multiple fetuses vary, but the di?erence between them and single fetuses are not that great until the later stages of pregnancy. Preterm labour is commoner in multiple pregnancies: the median length of pregnancy is 40 weeks for singletons, 37 for twins and 33 for triplets. Low birth-weights are usually the result of early delivery rather than abnormalities in growth rates. Women with multiple pregnancies require more frequent and vigilant antenatal assessments, with their carers being alert to the signs of preterm labour occurring. CEPHALOPELVIC DISPROPORTION Disparity between the size of the fetus and the mother’s pelvis is not common in the UK but is a signi?cant problem in the developing world. Disparity is classi?ed as absolute, when there is no possibility of delivery, and relative, when the baby is large but delivery (usually after a dif?cult labour) is possible. Causes of absolute disparity include: a large baby – heavier than 5 kg at birth; fetal HYDROCEPHALUS; and an abnormal maternal pelvis. The latter may be congenital, the result of trauma or a contraction in pelvic size because of OSTEOMALACIA early in life. Disproportion should be suspected if in late pregnancy the fetal head has not ‘engaged’ in the pelvis. Sometimes a closely supervised ‘trial of labour’ may result in a successful, if prolonged, delivery. Otherwise a caesarean section (see below) is necessary. UNUSUAL POSITIONS AND PRESENTATIONS OF THE BABY In most pregnant women the baby ?ts into the maternal pelvis head-?rst in what is called the occipito-anterior position, with the baby’s face pointing towards the back of the pelvis. Sometimes, however, the head may face the other way, or enter the pelvis transversely – or, rarely, the baby’s neck is ?exed backwards with the brow or face presenting to the neck of the womb. Some malpositions will correct naturally; others can be manipulated abdominally during pregnancy to a better position. If, however, the mother starts labour with the baby’s head badly positioned or with the buttocks instead of the head presenting (breech position), the labour will usually be longer and more di?cult and may require intervention using special obstetric forceps to assist in extracting the baby. If progress is poor and the fetus distressed, caesarean section may be necessary. HIV INFECTION Pregnant women who are HIV positive (see HIV; AIDS/HIV) should be taking antiviral drugs in the ?nal four to ?ve months of pregnancy, so as to reduce the risk of infecting the baby in utero and during birth by around 50 per cent. Additional antiviral treatment is given before delivery; the infection risk to the baby can be further reduced – by about 40 per cent – if delivery is by caesarean section. The mother may prefer to have the baby normally, in which case great care should be taken not to damage the baby’s skin during delivery. The infection risk to the baby is even further reduced if it is not breast fed. If all preventive precautions are taken, the overall risk of the infant becoming infected is cut to under 5 per cent.

Premature birth This is a birth that takes place before the end of the normal period of gestation, usually before 37 weeks. In practice, however, it is de?ned as a birth that takes place when the baby weighs less than 2·5 kilograms (5••• pounds). Between 5 and 10 per cent of babies are born prematurely, and in around 40 per cent of premature births the cause is unknown. Pre-eclampsia is the most common known cause; others include hypertension, chronic kidney disease, heart disease and diabetes mellitus. Multiple pregnancy is another cause. In the vast majority of cases the aim of management is to prolong the pregnancy and so improve the outlook for the unborn child. This consists essentially of rest in bed and sedation, but there are now several drugs, such as RITODRINE, that may be used to suppress the activity of the uterus and so help to delay premature labour. Prematurity was once a prime cause of infant mortality but modern medical care has greatly improved survival rates in developing countries.

Labour Also known by the traditional terms parturition, childbirth or delivery, this is the process by which the baby and subsequently the placenta are expelled from the mother’s body. The onset of labour is often preceded by a ‘show’ – the loss of the mucus and blood plug from the cervix, or neck of the womb; this passes down the vagina to the exterior. The time before the beginning of labour is called the ‘latent phase’ and characteristically lasts 24 hours or more in a ?rst pregnancy. Labour itself is de?ned by regular, painful contractions which cause dilation of the neck of the womb and descent of the fetal head. ‘Breaking of the waters’ is the loss of amniotic ?uid vaginally and can occur any time in the delivery process.

Labour itself is divided into three stages: the ?rst is from the onset of labour to full (10 cm) dilation of the neck of the womb. This stage varies in length, ideally taking no more than one hour per centimetre of dilation. Progress is monitored by regular vaginal examinations, usually every four hours. Fetal well-being is observed by intermittent or continuous monitoring of the fetal heart rate in relation to the timing and frequency of the contractions. The print-out is called a cardiotocograph. Abnormalities of the fetal heart rate may suggest fetal distress and may warrant intervention. In women having their ?rst baby (primigravidae), the common cause of a slow labour is uncoordinated contractions which can be overcome by giving either of the drugs PROSTAGLANDIN or OXYTOCIN, which provoke contractions of the uterine muscle, by an intravenous drip. Labours which progress slowly or not at all may be due to abnormal positioning of the fetus or too large a fetus, when prostaglandin or oxytocin is used much more cautiously.

The second stage of labour is from full cervical dilation to the delivery of the baby. At this stage the mother often experiences an irresistible urge to push the baby out, and a combination of strong coordinated uterine contractions and maternal e?ort gradually moves the baby down the birth canal. This stage usually lasts under an hour but can take longer. Delay, exhaustion of the mother or distress of the fetus may necessitate intervention by the midwife or doctor. This may mean enlarging the vaginal opening with an EPISIOTOMY (cutting of the perineal outlet – see below) or assisting the delivery with specially designed obstetric forceps or a vacuum extractor (ventouse). If the cervix is not completely dilated or open and the head not descended, then an emergency caesarean section may need to be done to deliver the baby. This procedure involves delivering the baby and placenta through an incision in the mother’s abdomen. It is sometimes necessary to deliver by planned or elective caesarean section: for example, if the placenta is low in the uterus – called placenta praevia – making a vaginal delivery dangerous.

The third stage occurs when the placenta (or afterbirth) is delivered, which is usually about 10–20 minutes after the baby. An injection of ergometrine and oxytocin is often given to women to prevent bleeding.

Pain relief in labour varies according to the mother’s needs. For uncomplicated labours, massage, reassurance by a birth attendant, and a warm bath and mobilisation may be enough for some women. However, some labours are painful, particularly if the woman is tired or anxious or is having her ?rst baby. In these cases other forms of analgesia are available, ranging from inhalation of NITROUS OXIDE GAS, injection of PETHIDINE HYDROCHLORIDE or similar narcotic, and regional local anaesthetic (see ANAESTHESIA).

Once a woman has delivered, care continues to ensure her and the baby’s safety. The midwives are involved in checking that the uterus returns to its normal size and that there is no infection or heavy bleeding, as well as caring for stitches if needed. The normal blood loss after birth is called lochia and generally is light, lasting up to six weeks. Midwives o?er support with breast feeding and care of the infant and will visit the parents at home routinely for up to two weeks.

Some complications of labour All operative deliveries in the UK are now done in hospitals, and are performed if a spontaneous birth is expected to pose a bigger risk to the mother or her child than a specialist-assisted one. Operative deliveries include caesarean section, forceps-assisted deliveries and those in which vacuum extraction (ventouse) is used. CAESAREAN SECTION Absolute indications for this procedure, which is used to deliver over 15 per cent of babies in Britain, are cephalopelvic disproportion and extensive placenta praevia, both discussed above. Otherwise the decision to undertake caesarean section depends on the clinical judgement of the specialist and the views of the mother. The rise in the proportion of this type of intervention (from 5 per cent in the 1930s to its present level of over 23 per cent


of the 600,000 or so annual deliveries in England) has been put down to defensive medicine

– namely, the doctor’s fear of litigation (initiated often because the parents believe that the baby’s health has su?ered because the mother had an avoidably di?cult ‘natural’ labour). In Britain, over 60 per cent of women who have had a caesarean section try a vaginal delivery in a succeeding pregnancy, with about two-thirds of these being successful. Indications for the operation include:

absolute and relative cephalopelvic disproportion.

placenta previa.

fetal distress.

prolapsed umbilical cord – this endangers the viability of the fetus because the vital supply of oxygen and nutrients is interrupted.

malpresentation of the fetus such as breech or transverse lie in the womb.

unsatisfactory previous pregnancies or deliveries.

a request from the mother.

Caesarean sections are usually performed using regional block anaesthesia induced by a spinal or epidural injection. This results in loss of feeling in the lower part of the body; the mother is conscious and the baby not exposed to potential risks from volatile anaesthetic gases inhaled by the mother during general anaesthesia. Post-operative complications are higher with general anaesthesia, but maternal anxiety and the likelihood that the operation might be complicated and di?cult are indications for using it. A general anaesthetic may also be required for an acute obstetric emergency. At operation the mother’s lower abdomen is opened and then her uterus opened slowly with a transverse incision and the baby carefully extracted. A transverse incision is used in preference to the traditional vertical one as it enables the woman to have a vaginal delivery in any future pregnancy with a much smaller risk of uterine rupture. Women are usually allowed to get up within 24 hours and are discharged after four or ?ve days. FORCEPS AND VENTOUSE DELIVERIES Obstetric forceps are made in several forms, but all are basically a pair of curved blades shaped so that they can obtain a purchase on the baby’s head, thus enabling the operator to apply traction and (usually) speed up delivery. (Sometimes they are used to slow down progress of the head.) A ventouse or vacuum extractor comprises an egg-cup-shaped metal or plastic head, ranging from 40 to 60 mm in diameter with a hollow tube attached through which air is extracted by a foot-operated vacuum pump. The instrument is placed on the descending head, creating a negative pressure on the skin of the scalp and enabling the operator to pull the head down. In mainland Europe, vacuum extraction is generally preferred to forceps for assisting natural deliveries, being used in around 5 per cent of all deliveries. Forceps have a greater risk of causing damage to the baby’s scalp and brain than vacuum extraction, although properly used, both types should not cause any serious damage to the baby.

Episiotomy Normal and assisted deliveries put the tissues of the genital tract under strain. The PERINEUM is less elastic than the vagina and, if it seems to be splitting as the baby’s head

moves down the birth canal, it may be necessary to cut the perineal tissue – a procedure called an episiotomy – to limit damage. This is a simple operation done under local anaesthetic. It should be done only if there is a speci?c indication; these include:

to hasten the second stage of labour if the fetus is distressed.

to facilitate the use of forceps or vacuum extractor.

to enlarge a perineum that is restricted because of unyielding tissue, perhaps because of a scar from a previous labour. Midwives as well as obstetricians are trained

to undertake and repair (with sutures) episiotomies.

(For organisations which o?er advice and information on various aspects of childbirth, including eclampsia, breast feeding and multiple births, see APPENDIX 2: ADDRESSES: SOURCES OF INFORMATION, ADVICE, SUPPORT AND SELF-HELP.)... Medical Dictionary

Medical Dictionary

A powerful muscle which arises from the front of the vertebral column in the lumbar region, and passes down, round the pelvis and through the groin, to be attached to the inner side of the thigh-bone not far from its upper end. The act of sitting up from a recumbent posture, or that of bending the thigh on the abdomen, is mainly accomplished by the contraction of this muscle. Disease of the spine in the lumbar region may produce an ABSCESS which lies within the sheath of this muscle and makes its way down to the front of the thigh. Such an abscess is known as a psoas abscess.... Medical Dictionary

Medical Dictionary

Pubis is the bone that forms the front part of the pelvis. The pubic bones of opposite sides meet in the symphysis and protect the bladder from the front.... Medical Dictionary

Medical Dictionary

The nerve that operates the lowest muscles of the ?oor of the PELVIS and also the anal SPHINCTER muscle. It may be damaged in childbirth, resulting in INCONTINENCE.... Medical Dictionary

Medical Dictionary

An inflammation of the kidney pelvis, the interface between the urine-secreting inner surface of the kidney and the muscular ureter that drains into the bladder. It can be caused by kidney stones or an infection that has progressed up from the lower urinary tract. It alone is a serious condition...the next stage, pyelonephritis, since it involves the whole kidney, is still worse.... Medical Dictionary

Herbal Medical

A term describing in?ammation of the pelvis of the kidney. In fact, the in?ammation usually a?ects the whole kidney tissue and the description should be PYELONEPHRITIS.... Herbal Medical

Medical Dictionary

Surgery to remove a stone from the kidney (see KIDNEYS, DISEASES OF) via an incision in the pelvis of the kidney.... Medical Dictionary

Medical Dictionary

The last part of the large INTESTINE. It pursues a more or less straight course downwards through the cavity of the pelvis, lying against the sacrum at the back of this cavity. This section of the intestine is about 23 cm (9 inches) long: its ?rst part is freely movable and corresponds to the upper three pieces of the sacrum; the second part corresponds to the lower two pieces of the sacrum and the coccyx; whilst the third part, known also as the anal canal, is about 25 mm (1 inch) long, runs downwards and backwards, and is kept tightly closed by the internal and external SPHINCTER muscles which surround it. The opening to the exterior is known as the ANUS. The structure of the rectum is similar to that of the rest of the intestine.... Medical Dictionary

Medical Dictionary

Movement in a contrary or backward direction from normal (e.g. a retrograde pyelogram introduces dye into the pelvis of the kidney by passing it up the ureters).... Medical Dictionary

Medical Dictionary

The portion of the SPINAL COLUMN near its lower end. The sacrum consists of ?ve vertebrae fused together to form a broad triangular bone which lies between the two haunch-bones and forms the back wall of the pelvis.... Medical Dictionary

Medical Dictionary

Pain in the distribution of the sciatic nerve. It is often accompanied by pain in the back, or LUMBAGO. In the majority of cases, however, it is due to a PROLAPSED INTERVERTEBRAL DISC in the lower part of the SPINAL CORD. What probably happens is that degenerative changes take place in the annulus ?brosus (see SPINAL COLUMN) as a result of some special strain – caused, for example, by heavy lifting – or spontaneously. The cushioning disc between the two neighbouring vertebral bodies slips through the rent in the annulus ?brosus, and presses on the neighbouring roots, thus causing the pain. The precise distribution of the pain will thus depend on which of the nerve roots are a?ected. As a rule, the pain is felt in the buttock, the back of the thigh and the outside and front of the leg, sometimes extending on to the top of the foot, the back of the thigh and the calf, and then along the outer border of the foot towards the little toe.

Rare causes include a tumour in the spine or spinal column, tuberculosis of the spine, ankylosing spondylitis (see SPINE AND SPINAL CORD, DISEASES AND INJURIES OF) or a tumour in one of the organs in the pelvis such as the UTERUS.

Treatment consists essentially of rest in bed in the early stages until the acute phase is over. ANALGESICS, such as aspirin and codeine, are given to relieve the pain. Expert opinion varies as to the desirability of wearing a PLASTER OF PARIS jacket or a specially made corset; also, as to the desirability of manipulation of the spine and operation. Surgeons are selective about which patients might bene?t from a LAMINECTOMY (removal of the protruding disc).... Medical Dictionary

Medical Dictionary

A branched renal stone formed in the image of the collecting system of the kidney (see KIDNEYS). It ?lls the calyces and pelvis and is commonly associated with an infection of the urine, particularly Proteus vulgaris. The calculus may lead to pyonephrosis and an ABSCESS of the kidney.... Medical Dictionary

Medical Dictionary

6.5 cm wide, 5 cm thick, and weighs around 140 grams.

Adult kidneys have a smooth exterior, enveloped by a tough ?brous coat that is bound to the kidney only by loose ?brous tissue and by a few blood vessels that pass between it and the kidney. The outer margin of the kidney is convex; the inner is concave with a deep depression, known as the hilum, where the vessels enter. The URETER, which conveys URINE to the URINARY BLADDER, is also joined at this point. The ureter is spread out into an expanded, funnel-like end, known as the pelvis, which further divides up into little funnels known as the calyces. A vertical section through a kidney (see diagram) shows two distinct layers: an outer one, about 4 mm thick, known as the cortex; and an inner one, the medulla, lying closer to the hilum. The medulla consists of around a dozen pyramids arranged side by side, with their base on the cortex and their apex projecting into the calyces of the ureter. The apex of each pyramid is studded with tiny holes, which are the openings of the microscopic uriniferous tubes.

In e?ect, each pyramid, taken together with the portion of cortex lying along its base, is an independent mini-kidney. About 20 small tubes are on the surface of each pyramid; these, if traced up into its substance, repeatedly subdivide so as to form bundles of convoluted tubules, known as medullary rays, passing up towards the cortex. One of these may be traced further back, ending, after a tortuous course, in a small rounded body: the Malpighian corpuscle or glomerulus (see diagram). Each glomerulus and its convoluted tubule is known as a nephron, which constitutes the functional unit of the kidney. Each kidney contains around a million nephrons.

After entering the kidney, the renal artery divides into branches, forming arches where the cortex and medulla join. Small vessels come o? these arches and run up through the cortex, giving o? small branches in each direction. These end in a tuft of capillaries, enclosed in Bowman’s capsule, which forms the end of the uriniferous tubules just described; capillaries with capsule constitute a glomerulus.

After circulating in the glomerulus, the blood leaves by a small vein, which again divides into capillaries on the walls of the uriniferous tubules. From these it is ?nally collected into the renal veins and then leaves the kidney. This double circulation (?rst through the glomerulus and then around the tubule) allows a large volume of ?uid to be removed from the blood in the glomerulus, the concentrated blood passing on to the uriniferous tubule for removal of parts of its solid contents. Other arteries come straight from the arches and supply the medulla direct; the blood from these passes through another set of capillaries and ?nally into the renal veins. This circulation is con?ned purely to the kidney, although small connections by both arteries and veins exist which pass through the capsule and, joining the lumbar vessels, communicate directly with the aorta.

Function The kidneys work to separate ?uid and certain solids from the blood. The glomeruli ?lter from the blood the non-protein portion of the plasma – around 150–200 litres in 24 hours, 99 per cent of which is reabsorbed on passing through the convoluted tubules.

Three main groups of substances are classi?ed according to their extent of uptake by the tubules:

(1) SUBSTANCES ACTIVELY REABSORBED These include amino acids, glucose, sodium, potassium, calcium, magnesium and chlorine (for more information, see under separate entries).

(2) SUBSTANCES DIFFUSING THROUGH THE TUBULAR EPITHELIUM when their concentration in the ?ltrate exceeds that in the PLASMA, such as UREA, URIC ACID and phosphates.

(3) SUBSTANCES NOT RETURNED TO THE BLOOD from the tubular ?uid, such as CREATINE, accumulate in kidney failure, resulting in general ‘poisoning’ known as URAEMIA.... Medical Dictionary

Medical Dictionary

An anatomical description of a joint in which two bones are connected by strong ?brous cartilage. One example is the joint between the two pubic bones in the front of the pelvis; another, the joint between the upper and middle parts of the breastbone.... Medical Dictionary

Beneficial Teas

Abortion is a medical procedure of ending a pregnancy during its first 24 weeks. There are several reasons why this medical process is carried out: a fetus’ or woman’s health issue or, most frequent, there are personal considerations which impede the woman to keep the baby. No matter the reasons of an abortion, it should be made by a physician. Also, the woman’s post-abortion state requires medical observation, because there have been acknowledged physical and psychological effects after this medical condition. Like any other medical procedure, abortion implies risks, like losing a large amount of blood (haemorrhage) or inflammation of the pelvis. Studies revealed that further miscarriages can be associated with earlier abortions, as the surgery may lead to the damage of the womb. A pregnancy can be ended by a medical procedure or, by a traditional method, like drinking teas causing abortion. How Tea for Abortion works There are two categories of tea which lead to ending a pregnancy: emmenagogue and abortifacient teas. The first type of tea induces woman’s period to start, whereas the second one causes painful contractions of the uterus, followed by abortion. Teas leading to Abortion Please read the list of some of the teas you should not drink if you are pregnant or, you try to become pregnant. Blue Cohosh is a wood plant, growing in New England (United States) and also in Canada. It has anti-inflammatory and antispasmodic properties. It is generally used to treat rheumatism and to prevent osteoporosis. Muscles aches caused by physical effort are relieved by taking Blue Cohosh as tea, tincture or decoction. It cannot stimulate the estrogen production thus, the body is not able to provide the endometrial and uterine growth, leading to contractions of the uterine and, finally, to a painful abortion. Unfortunately, Blue Cohosh tea has been used for a long period of time as a medicinal and home-made beverage for abortion. Pennyroyal is a plant from the mint family, whose essential oil is toxic if taken internally. In the past, women were poisoning themselves in the attempt of ending the pregnancy. Taken as an infusion, the plant is efficient in mitigating the unpleasant feelings of the upset stomach, abdominal cramps , as well as colds. Pennyroyal tea should not be drunk by pregnant women or by those who want to become pregnant, because it irritates the uterus, causing contractions and, of course, abortion. Tansy is a herbaceous plant, originating from Europe, but also cultivated in the United States. It is best known for its action as an insect repellant, being used as treatment against worms. It is a digestion adjuvant as well as a migraine reliever. Tansy tea provides contractions of the uterus and abortion, which can be so violent that causes death, just like the above mentioned teas causing abortion. Uterine bleeding, nausea and loss of consciousness are some of the signs displayed by people who had ingested a large dose of the beverage. Women should bear in mind that these three types of tea are scientifically proven to cause abortion. So, they should not consume them! Furthermore, women should ask their doctor for a list of the edible products while pregnancy, in order to avoid unpleasant situations of any kind.  ... Beneficial Teas

Medical Dictionary

The portion of the lower limb above the knee. The thigh is supported by the femur or thighbone, the longest and strongest bone in the body. A large four-headed muscle, the quadriceps, forms most of the ?eshy mass on the front and sides of the thigh and serves to straighten the leg in walking as well as to maintain the erect posture of the body in standing. At the back of the thigh lie the hamstring muscles; on the inner side the adductor muscles, attached above to the pelvis and below to the femur, pull the lower limb inwards. The large femoral vessels emerge from the abdomen in the middle of the groin, the vein lying to the inner side of the artery. These pass downwards and inwards deeply placed between the muscles, and at the knee they lie behind the joint. The great saphenous vein lies near the surface and can be seen towards the inner side of the thigh passing up to the groin, where it joins the femoral vein. The femoral nerve accompanies the large vessels and controls the muscles on the front and inner side of the thigh; while the large sciatic nerve lies close to the back of the femur and supplies the muscles at the back of the thigh and muscles below the knee.

Deep wounds on the inner side of the thigh are dangerous by reason of the risk of damage to the large vessels. Pain in the back of the thigh is often due to in?ammation of the sciatic nerve (see SCIATICA). The veins on the inner side of the thigh are specially liable to become dilated.... Medical Dictionary

Medical Dictionary

This is a steep head-down tilt so that the patient’s pelvis and legs lie above the heart. It is used to improve access, and to limit blood loss, during surgery to the pelvis. It has been used to treat shocked patients (see SHOCK), but, as the position increases pressure on the DIAPHRAGM and embarrasses breathing, raising the legs by themselves is better.... Medical Dictionary

Medical Dictionary

The tube that carries URINE from the kidney (see KIDNEYS) to the URINARY BLADDER. There are two ureters, one for each kidney, and they originate from the kidney pelvis and track for 25– 30 cm (10–12 inches) through the loins and pelvis. They open by a narrow slit into the base of the bladder. The lower end of the ureter pierces the wall of the bladder so obliquely (lying embedded in the wall for about 21 mm) that, although urine runs freely into the bladder, it is prevented from returning up the ureter as the bladder becomes distended.... Medical Dictionary

Medical Dictionary

A ?exible or rigid endoscopic instrument (see ENDOSCOPE) that is inserted (via the URINARY BLADDER) into the URETER and up into the pelvis of the kidney (see KIDNEYS). The instrument is commonly used to identify a stone in the ureter and to remove it under vision with forceps or a stone basket. If the stone is large it is broken into fragments, using an ultrasound or electrohydraulic LITHOTRIPSY probe that is inserted through the instrument.... Medical Dictionary

Medical Dictionary

Trauma Injury to the urethra is often the result of severe trauma to the pelvis – for example, in a car accident or as the result of a fall. Trauma can also result from catheter insertion (see CATHETERS) or the insertion of foreign bodies into the urethra. The signs are the inability to pass urine, and blood at the exit of the urethra. The major complication of trauma is the development of a urethral stricture (see below).

Urethritis is in?ammation of the urethra from infection.

Causes The sexually transmitted disease GONORRHOEA a?ects the urethra, mainly in men, and causes severe in?ammation and urethritis. Non-speci?c urethritis (NSU) is an in?ammation of the urethra caused by one of many di?erent micro-organisms including BACTERIA, YEAST and CHLAMYDIA.

Symptoms The classic signs and symptoms are a urethral discharge associated with urethral pain, particularly on micturition (passing urine), and DYSURIA.

Treatment This involves taking urethral swabs, culturing the causative organism and treating it with the appropriate antibiotic. The complications of urethritis include stricture formation.

Stricture This is an abrupt narrowing of the urethra at one or more places. Strictures can be a result of trauma or infection or a congenital abnormality from birth. Rarely, tumours can cause strictures.

Symptoms The usual presenting complaint is one of a slow urinary stream. Other symptoms include hesitancy of micturition, variable stream and terminal dribbling. Measurement of the urine ?ow rate may help in the diagnosis, but often strictures are detected during cystoscopy (see CYSTOSCOPE).

Treatment The traditional treatment was the periodic dilation of the strictures with ‘sounds’

– solid metal rods passed into the urethra. However, a more permanent solution is achieved by cutting the stricture with an endoscopic knife (optical urethrotomy). For more complicated long or multiple strictures, an open operation (urethroplasty) is required.... Medical Dictionary

Medical Dictionary

The urinary bladder is a highly distensible organ for storing URINE. It consists of smooth muscle known as the detrusor muscle and is lined with urine-proof cells known as transitional cell epithelium.

The bladder lies in the anterior half of the PELVIS, bordered in front by the pubis bone and laterally by the side wall of the pelvis. Superiorly the bladder is covered by the peritoneal lining of the abdomen. The bottom or base of the bladder lies against the PROSTATE GLAND in the male and the UTERUS and VAGINA in the female.... Medical Dictionary

Medical Dictionary

A hollow, triangular organ, ?attened from front to back, the lower angle (or cervix) commincates through a narrow opening (the os uteri) with the VAGINA. The uterus or womb is where the fertilised ovum (egg) normally becomes embedded and in which the EMBRYO and FETUS develop. The normal uterus weighs 30–40 g; during pregnancy, however, enormous growth occurs together with muscular thickening (see MUSCLE – Development of muscle). The cavity is lined by a thick, soft, mucous membrane, and the wall is chie?y composed of muscle ?bres arranged in three layers. The outer surface, like that of other abdominal organs, is covered by a layer of PERITONEUM. The uterus has a copious supply of blood derived from the uterine and ovarian arteries. It has also many lymphatic vessels, and its nerves establish wide connections with other organs (see PAIN). The position of the uterus is in the centre of the PELVIS, where it is suspended by several ligaments between the URINARY BLADDER in front and the RECTUM behind. On each side of the uterus are the broad ligaments passing outwards to the side of the pelvis, the utero-sacral ligament passing back to the sacral bone, the utero-vesical ligament passing forwards to the bladder, and the round ligament uniting the uterus to the front of the abdomen.... Medical Dictionary

Medical Dictionary

Absence or defects of the uterus

Rarely, the UTERUS may be completely absent as a result of abnormal development. In such patients secondary sexual development is normal but MENSTRUATION is absent (primary amennorhoea). The chromosomal make-up of the patient must be checked (see CHROMOSOMES; GENES): in a few cases the genotype is male (testicular feminisation syndrome). No treatment is available, although the woman should be counselled.

The uterus develops as two halves which fuse together. If the fusion is incomplete, a uterine SEPTUM results. Such patients with a double uterus (uterus didelphys) may have fertility problems which can be corrected by surgical removal of the uterine septum. Very rarely there may be two uteri with a double vagina.

The uterus of most women points forwards (anteversion) and bends forwards (ante?exion). However, about 25 per cent of women have a uterus which is pointed backwards (retroversion) and bent backwards (retro?exion). This is a normal variant and very rarely gives rise to any problems. If it does, the attitude of the uterus can be corrected by an operation called a ventrosuspension.

Endometritis The lining of the uterine cavity is called the ENDOMETRIUM. It is this layer that is partially shed cyclically in women of reproductive age giving rise to menstruation. Infection of the endometrium is called endometritis and usually occurs after a pregnancy or in association with the use of an intrauterine contraceptive device (IUCD – see CONTRACEPTION). The symptoms are usually of pain, bleeding and a fever. Treatment is with antibiotics. Unless the FALLOPIAN TUBES are involved and damaged, subsequent fertility is una?ected. Very rarely, the infection is caused by TUBERCULOSIS. Tuberculous endometritis may destroy the endometrium causing permanent amenorrhoea and sterility.

Menstrual disorders are common. Heavy periods (menorrhagia) are often caused by ?broids (see below) or adenomyosis (see below) or by anovulatory cycles. Anovulatory cycles result in the endometrium being subjected to unopposed oestrogen stimulation and occasionally undergoing hyperplasia. Treatment is with cyclical progestogens (see PROGESTOGEN) initially. If this form of treatment fails, endoscopic surgery to remove the endometrium may be successful. The endometrium may be removed using LASER (endometrial laser ablation) or electrocautery (transcervical resection of endometrium). Hysterectomy (see below) will cure the problem if endoscopic surgery fails. Adenomyosis is a condition in which endometrial tissue is found in the muscle layer (myometrium) of the uterus. It usually presents as heavy and painful periods, and occasionally pain during intercourse. Hysterectomy is usually required.

Oligomenorhoea (scanty or infrequent periods) may be caused by a variety of conditions including thyroid disease (see THYROID GLAND, DISEASES OF). It is most commonly associated with usage of the combined oral contraceptive pill. Once serious causes have been eliminated, the patient should be reassured. No treatment is necessary unless conception is desired, in which case the patient may require induction of ovulation.

Primary amenorrhoea means that the patient has never had a period. She should be investigated, although usually it is only due to an inexplicable delay in the onset of periods (delayed menarche) and not to any serious condition. Secondary amenorrhoea is the cessation of periods after menstruation has started. The most common cause is pregnancy. It may be also caused by endocrinological or hormonal problems, tuberculous endometritis, emotional problems and severe weight loss. The treatment of amenorrhoea depends on the cause.

Dysmenorrhoea, or painful periods, is the most common disorder; in most cases the cause is unknown, although the disorder may be due to excessive production of PROSTAGLANDINS.

Irregular menstruation (variations from the woman’s normal menstrual pattern or changes in the duration of bleeding or the amount) can be the result of a disturbance in the balance of OESTROGENS and PROGESTERONE hormone which between them regulate the cycle. For some time after the MENARCHE or before the MENOPAUSE, menstruation may be irregular. If irregularity occurs in a woman whose periods are normally regular, it may be due to unsuspected pregnancy, early miscarriage or to disorders in the uterus, OVARIES or pelvic cavity. The woman should seek medical advice.

Fibroids (leiomyomata) are benign tumours arising from the smooth muscle layer (myometrium) of the uterus. They are found in 80 per cent of women but only a small percentage give rise to any problems and may then require treatment. They may cause heavy periods and occasionally pain. Sometimes they present as a mass arising from the pelvis with pressure symptoms from the bladder or rectum. Although they can be shrunk medically using gonadorelin analogues, which raise the plasma concentrations of LUTEINISING HORMONE and FOLLICLE-STIMULATING HORMONE, this is not a long-term solution. In any case, ?broids only require treatment if they are large or enlarging, or if they cause symptoms. Treatment is either myomectomy (surgical removal) if fertility is to be retained, or a hysterectomy.

Uterine cancers tend to present after the age of 40 with abnormal bleeding (intermenstrual or postmenopausal bleeding). They are usually endometrial carcinomas. Eighty per cent present with early (Stage I) disease. Patients with operable cancers should be treated with total abdominal hysterectomy and bilateral excision of the ovaries and Fallopian tubes. Post-operative RADIOTHERAPY is usually given to those patients with adverse prognostic factors. Pre-operative radiotherapy is still given by some centres, although this practice is now regarded as outdated. PROGESTOGEN treatment may be extremely e?ective in cases of recurrence, but its value remains unproven when used as adjuvant treatment. In 2003 in England and Wales, more than 2,353 women died of uterine cancer.

Disorders of the cervix The cervix (neck of the womb) may produce an excessive discharge due to the presence of a cervical ectopy or ectropion. In both instances columnar epithelium – the layer of secreting cells – which usually lines the cervical canal is exposed on its surface. Asymptomatic patients do not require treatment. If treatment is required, cryocautery – local freezing of tissue – is usually e?ective.

Cervical smears are taken and examined in the laboratory to detect abnormal cells shed from the cervix. Its main purpose is to detect cervical intraepithelial neoplasia (CIN) – the presence of malignant cells in the surface tissue lining the cervix – since up to 40 per cent of women with this condition will develop cervical cancer if the CIN is left untreated. Women with abnormal smears should undergo colposcopy, a painless investigation using a low-powered microscope to inspect the cervix. If CIN is found, treatment consists of simply removing the area of abnormal skin, either using a diathermy loop or laser instrument.

Unfortunately, cervical cancer remains the most common of gynaecological cancers. The most common type is squamous cell carcinoma and around 4,000 new cases (all types) are diagnosed in England and Wales every year. As many as 50 per cent of the women a?ected may die from the disease within ?ve years. Cervical cancer is staged clinically in four bands according to how far it has extended, and treatment is determined by this staging. Stage I involves only the mucosal lining of the cervix and cone BIOPSY may be the best treatment in young women wanting children. In Stage IV the disease has spread beyond the cervix, uterus and pelvis to the URINARY BLADDER or RECTUM. For most women, radiotherapy or radical Wertheim’s hysterectomy – the latter being preferable for younger women – is the treatment of choice if the cancer is diagnosed early, both resulting in survival rates of ?ve years in 80 per cent of patients. Wertheim’s hysterectomy is a major operation in which the uterus, cervix, upper third of vagina and the tissue surrounding the cervix are removed together with the LYMPH NODES draining the area. The ovaries may be retained if desired. Patients with cervical cancer are treated by radiotherapy, either because they present too late for surgery or because the surgical skill to perform a radical hysterectomy is not available. These operations are best performed by gynaecological oncologists who are gynaecological surgeons specialising in the treatment of gynaecological tumours. The role of CHEMOTHERAPY in cervical and uterine cancer is still being evaluated.

Prolapse of the uterus is a disorder in which the organ drops from its normal situation down into the vagina. First-degree prolapse is a slight displacement of the uterus, second-degree a partial displacement and third-degree when the uterus can be seen outside the VULVA. It may be accompanied by a CYSTOCOELE (the bladder bulges into the front wall of the vagina), urethrocoele (the urethra bulges into the vagina) and rectocoele (the rectal wall bulges into the rear wall of the vagina). Prolapse most commonly occurs in middle-aged women who have had children, but the condition is much less common now than in the past when prenatal and obstetric care was poor, women had more pregnancies and their general health was poor. Treatment is with pelvic exercises, surgical repair of the vagina or hysterectomy. If the woman does not want or is not ?t for surgery, an internal support called a pessary can be ?tted – and changed periodically.

Vertical section of female reproductive tract (viewed from front) showing sites of common gynaecological disorders.

Hysterectomy Many serious conditions of the uterus have traditionally been treated by hysterectomy, or removal of the uterus. It remains a common surgical operation in the UK, but is being superseded in the treatment of some conditions, such as persistent MENORRHAGIA, with endometrial ablation – removal of the lining of the uterus using minimally invasive techniques, usually using an ENDOSCOPE and laser. Hysterectomy is done to treat ?broids, cancer of the uterus and cervix, menorrhagia, ENDOMETRIOSIS and sometimes for severely prolapsed uterus. Total hysterectomy is the usual type of operation: it involves the removal of the uterus and cervix and sometimes the ovaries. After hysterectomy a woman no longer menstruates and cannot become pregnant. If the ovaries have been removed as well and the woman had not reached the menopause, hormone replacement therapy (HRT – see MENOPAUSE) should be considered. Counselling helps the woman to recover from the operation which can be an emotionally challenging event for many.... Medical Dictionary

Medical Dictionary

The back ?ow of URINE from the URINARY BLADDER into the ureters (see URETER). The cause is defects in the VALVES which normally prevent this re?ux from occurring. If, in addition, the patient – usually a child – acquires bacteria in the bladder, the consequence may be one or more attacks of PYELONEPHRITIS caused by the infected urine gaining access to the kidney pelvis. Diagnosis is by imaging techniques. Treatment is by long-term antibiotics while awaiting spontaneous recovery. Occassionally, corrective surgery is required.... Medical Dictionary

Medical Dictionary

A false communication between the URINARY BLADDER and the VAGINA. The result is urinary INCONTINENCE. Surgical damage to the bladder during operations for gynaecological disorders is one possible cause. Another is tissue damage following radiotherapy for cancer in the pelvis.... Medical Dictionary