破产前发生理赔次数
the number of claims occurring up to ruin
着床前发育
early embryonic development
产程和分娩并发前置血管
Labour and delivery complicated by vasa praevia
产前暴露迟发效应
Prenatal exposure delayed effects
产前超声检查
Prenatal ultrasonography
Ultrosound exposure to pregnant women
Prenatal ultasonography
产前超声筛查
Prenatal ultrasound scans
产前超声预测
antepartum ultrasonic prediction