Uterine trauma and limb defects.

The temporary clamping of the uterine blood vessels on one side of the uterus during late pregnancy in the rat (days 14-16) results in hemorrhage and tissue necrosis in the extremities of the fetuses from the experimental side and occasionally from the control side. A further series of experiments showed that similar fetal hemorrhage followed the temporary clamping (45 minutes) of the uterine wall or uterine fat, excluding major uterine vessels; handling the uterus for 5 minutes; and stretching of the uterine blood vessels. A low incidence of fetal hemorrhage was also associated with laparotomy alone, but the fetuses were unaffected by extensive handling of the uterus through the abdominal wall or by intraperitoneal anesthesia. Fetal hemorrhage was also induced by a short episode of severe maternal hyperthermia but not by a high dose of ethanol given by gavage. These results suggest that a range of uterine trauma may result in fetal hemorrhage, perhaps through a common mechanism.