If it doesn't embed, a few days later the body's progesterone and estrogen levels plummet, meaning the womb stops padding out and starts to degenerate, eventually falling away.

如果卵子没有成功着床， 几天后体体素和雌激素水平会急剧下降，这意味着子宫停止增厚并开始退化，最终脱落。

Meanwhile, the now-empty follicle begins to release progesterone, another hormone that tells the womb's lining to plump up with blood and nutrients, in preparation for a fertilized egg that may embed there and grow.

与此同时， 空卵子卵泡开始分泌体素，这是一种告知子宫充盈血液和营养激素，为可能在此着床并成长受精卵做好准备。