Conclusion caesarean section for first live birth is associated with a 47 % increased risk of placenta praevia and 40 % increased risk of placental abruption in second pregnancy with a singleton 结论：首次分娩采用剖宫产女性在第二次怀孕（单胎）发生前置胎盘和胎盘早剥风险分别增加了47 % 、 40 % 。
