High estradiol in women after pregnancy is usually due to good ovarian endocrine function or multiple pregnancies and is usually normal. Estradiol is a hormone that promotes the growth of the endometrium. An elevated level of estradiol in early pregnancy indicates that the endometrium grows thicker, which is conducive to embryo implantation and growth. If estradiol decreases, the endometrium will become thinner and the pregnant woman will be prone to preterm miscarriage. The ovaries secrete estradiol after pregnancy, and when the placenta grows in the third trimester, the placenta replaces the endocrine function of the ovaries, thus causing an increase in estradiol in the body. Therefore, an increase in estradiol in the first trimester of pregnancy usually indicates good endocrine function of the ovaries and indirectly reflects good embryonic growth and development. If estradiol is higher than the normal value, it is usually considered a multiple pregnancy, when the ovaries need to secrete a large amount of estrogen to promote the growth and development of the embryo, and therefore the amount of hormone secreted is significantly higher. In general, the levels of HCG, progesterone and estradiol should be monitored in early pregnancy. The increase of estradiol basically has no effect on women, as it can promote the growth and development of the embryo and will not cause abnormalities such as fetal malformation. Therefore, if the blood HCG and estradiol are elevated, the pregnant woman does not need to be anxious and only needs to undergo ultrasound examination after 45 days of menopause to observe the normal growth and development of the embryo in the uterus.