After pregnancy, there will be no more follicles in the ovaries to mature and expel the eggs. This is because after pregnancy the ovaries secrete estrogen and progesterone in a continuous manner rather than in a non-pregnant cycle. Therefore, after pregnancy, there will be no more follicle growth and development in the ovaries. In the third trimester, after the placenta is formed, the body depends on the placental tissue for the secretion of estrogen and progesterone. Therefore, during the entire pregnancy, ovulation will not occur and the endometrium will not change periodically. It is recommended to have regular checkups during pregnancy. You can go to the hospital in your third trimester to build a maternity health card, and bring it with you during each pregnancy checkup to help your doctor understand the previous checkups.