The reasons for the decrease of progesterone and estradiol in early pregnancy include luteal insufficiency and embryonic dysplasia, which can be actively treated under the guidance of doctors. 1. Luteal insufficiency: When the luteal body is not functioning properly, progesterone and estradiol will drop in early pregnancy, and in severe cases, irregular vaginal bleeding, paroxysmal lower abdominal pain and other symptoms of miscarriage may occur. Ultrasound examination of the embryo development is normal, combined with the history and laboratory tests can help diagnosis, need to follow the doctor’s instructions to give progesterone, estradiol tablets and other drugs to protect the fetus treatment. 2. Embryonic dysplasia: When ultrasound suggests embryonic dysplasia, it will also cause a decrease in the levels of progesterone and estradiol, and ultrasound suggests that the development of the gestational sac or fetal buds does not correspond to the actual gestational week, so dynamic review is needed to understand the development of the embryo. When progesterone and estradiol levels drop in early pregnancy, you need to find out the cause under the guidance of your doctor and give timely treatment.