Abstract:Objective To discuss the causes of prenatal bleeding and the clinical value of prenatal ultrasound examination. Methods The antenatal test and delivery data of 2,490 pregnant women, who had routine pregnancy examination in the Obstetrics and Gynecology Outpatient Department and childbirth in the Obstetrical Ward of our hospital, were retrospectively analyzed. According to the history of vaginal bleeding from the 20th week of pregnancy to the time before delivery the pregnant women were divided into hemorrhagic group of 229 cases and non-hemorrhagic group of 2,261 cases. The clinical data and birth outcome were compared between the two groups. The causes of prenatal bleeding and the value of ultrasonography in the hemorrhagic group were analyzed. Results There was no significant difference in age or twin pregnancy rate between the bleeding group and the non-bleeding group (P > 0.05). The pregnant time, the average value of delivery, the history of abortion and the history of cesarean section in the bleeding group were significantly higher than those in the non-bleeding group (P < 0.05). The main causes of prenatal hemorrhage were placenta previa (104/229, 45.41%), placental abruption (61/229, 26.64%), placenta previa and placenta implantation (30/229, 13.10%). The diagnosis rate of prenatal ultrasound diagnosis was as follows: placenta previa 90.38% (94/104), placental abruption 78.69% (48/61), placenta previa and placenta implantation 66.67% (20/30), placenta implantation 71.43% (5/7) and uterine rupture 71.43% (5/7). The rates of cesarean section, premature delivery, uterine resection and postpartum hemorrhage, neonatal mortality, and birth rate of low-birth weight infant in the bleeding group were significantly higher than those in the non-bleeding group (P < 0.05). Conclusions The main causes of prenatal bleeding are placenta previa, placenta abruption, and so on. The diagnostic accuracy of ultrasonography is fairly high. The incidence of adverse birth outcomes is higher in pregnant women with prenatal hemorrhage.