蜕膜

例句：

1. 1. The embryonic membranes gradually dissolve during the first trimester of pregnancy.
   胚胎膜在怀孕的前三个月逐渐溶解。
2. 2. During labor, the uterine wall is stretched and the fetal membranes separate from the uterus.
   分娩时，子宫壁被拉伸，胎儿膜与子宫分离。
3. 3. The amniotic sac contains fluid that protects the developing fetus and provides nutrients for itsgrowth.
   羊水囊含有液体，保护正在发育的胎儿并提供其生长所需的营养。