Estradiol plug in early pregnancy can play a role in supplementing estrogen and promoting the growth of endometrium. Estradiol can promote the growth of uterine lining in the early stage of pregnancy, which can provide a good environment for the fertilized egg to settle and embryo to grow and develop. Low estradiol or thin uterine lining can easily cause preeclampsia. Estradiol tablets can play the role of supplementing estrogen and promoting the growth of endometrium after plugging the vagina, which can reduce the incidence of preeclampsia. In addition, if endocrine disorders and lowered hormone levels occur during IVF, estradiol tablets can also be used as prescribed by doctor to supplement estrogen and increase the success rate of IVF. In the early stage of pregnancy, estradiol tablets should not be used without authorization, and if there is low estrogen or thin endometrium, the medication should be used in strict accordance with the doctor’s prescription, and pay attention to follow up the development of the fetus.