本文报道一例孕妇，孕32周n +4超声检查首次发现胎儿下腹部低回声区，复查超声考虑胎儿泄殖腔发育异常。孕38周n +2先兆临产，剖宫产分娩一女婴，出生体重3 100 g，1 min Apgar评分10分。新生儿体格检查未见处女膜孔，超声和MRI检查诊断处女膜闭锁合并子宫阴道积液。生后2 d穿刺引流出70 ml乳白色液体。生后30 d于外院行处女膜切开引流术，术后患儿恢复良好。n “,”We report a pregnant woman who was found with fetal lower abdominal hypoechoic sign by ultrasonography at 32n +4 gestational weeks, and a fetal cloaca heteroplasia was considered at the second ultrasound scan. A girl weighing 3 100 g was born by cesarean section at 38n +2 weeks of gestation with the Apgar score of 10 at one minute after birth. Postnatal physical examination revealed imperforate hymen, and neonatal imperforate hymen with hydrometrocolpos was diagnosed by ultrasound and MRI. Puncture drainage of 70 ml milky white fluid was performed 2 days after birth. The girl underwent hymenotomy and drainage in another hospital 30 days after birth and recovered later.n