Conclusion Placental function decreased while risks for fetus increased as the gestation delayed.Therefore,to ensure the safety of mother and child,delayed gestation should be closely moni...

• 结论延期妊娠时胎盘功能逐渐降低、胎儿高危程度逐渐增加,故产前、产时应严密监护及时处理,以确保母婴安全。