一些声像图研究表明,在妊娠前半期伴有阴道流血的患者中可见到绒毛膜下血肿。在声像图中,该血肿表现为羊膜外宫腔内的无或低回声区,常使胎盘边缘与子宫壁分离。以往,有关血肿发生率的报道不多,而对自然流产的危险性却众说纷纭。作者在1980～1987年间通过超声检查对342名妊娠9～20周伴有阴道流血但胎儿存活的妇女进行了前瞻性研究,以确定绒毛膜下血肿在此类患者中的发生率及意义。以公式长×宽×厚×0.5计算绒毛膜下血肿的容积,每隔一或二周作一次超声检查,直到血肿消失。除外血肿小于2 ml者。根据声像图测得的头臀长度和双顶径估计胎龄。在最初 Some sonogram studies have shown that sub-subdural hematomas are seen in patients with vaginal bleeding in the first trimester of pregnancy. In the sonography, the hematoma showed no or low echo within the amniotic uterine cavity, often leaving the edge of the placenta and uterine wall separation. In the past, few reports on the incidence of hematoma, but the risk of spontaneous abortion, but different opinions. The authors conducted a prospective study of 342 women with vaginal bleeding but fetal survival at 9-20 weeks of gestation by means of ultrasound in 1980-1987 to determine the incidence and significance of sub-serous hematoma in such patients. To the formula length × width × thickness × 0.5 calculate the volume of subdural hematoma, every one or two weeks for an ultrasound examination, until the hematoma disappeared. Except hematoma less than 2 ml. According to the sonography measured head and hip length and biparietal diameter of estimated gestational age. At first