Placenta Praevia | Health Dictionary

Implantation of the PLACENTA in the bottom part of the UTERUS adjacent to or over the CERVIX. The condition may cause few problems during pregnancy or labour; it may, however, cause vaginal bleeding late in pregnancy or hinder vaginal delivery of the baby and this may necessitate obstetric intervention.


Placenta Praevia | Health Dictionary

Keywords of this word: Placenta Praevia


ABRUPTIO PLACENTA

Medical Dictionary

Placental bleeding after the 24th week of pregnancy, which may result in complete or partial detachment of the placenta from the wall of the womb. The woman may go into shock. The condition is sometimes associated with raised blood pressure and PRE-ECLAMPSIA. (See also PREGNANCY AND LABOUR.)... Medical Dictionary

PLACENTA

Medical Dictionary

The thick, spongy, disc-like mass of tissue which connects the EMBRYO with the inner surface of the UTERUS, the embryo otherwise lying free in the amniotic ?uid (see AMNION). The placenta is mainly a new structure growing with the embryo, but, when it separates, a portion of the inner surface of the womb – called the maternal placenta – comes away with it. It is mainly composed of loops of veins belonging to the embryo, lying in blood-sinuses, in which circulates maternal blood. Thus, although no mixing of the blood of embryo and mother takes place, there is ample opportunity for the exchange of ?uids, gases, and the nutrients brought by the mother’s blood. The width of the full-sized placenta is about 20 cm (8 inches), its thickness 2·5 cm (1 inch). One surface is rough and studded with villi, which consist of the loops of fetal veins; the other is smooth, and has implanted in its centre the umbilical cord, or navel string, which is about as thick as a ?nger and 50 cm (20 inches) long. It contains two arteries and a vein, enters the fetus at the navel, and forms the sole connection between the bodies of mother and fetus. The name ‘afterbirth’ is given to the structure because it is expelled from the womb in the third stage of labour (see PREGNANCY AND LABOUR).... Medical Dictionary

PLACENTA PRAEVIA

Medical Dictionary

Implantation of the PLACENTA in the bottom part of the UTERUS adjacent to or over the CERVIX. The condition may cause few problems during pregnancy or labour; it may, however, cause vaginal bleeding late in pregnancy or hinder vaginal delivery of the baby and this may necessitate obstetric intervention.... Medical Dictionary