Progesterone is a good indicator to monitor embryonic development: after 5-6 weeks of early pregnancy (from the first day of the last menstrual period), progesterone should reach 25ng/ml (25X3.18=79nmol/L) or more. 20ng/ml is a slightly lower level, which can be reversed if the adverse factors are corrected at this time. Progesterone below 15ng/ml is an indicator of danger, when the trend of embryonic dysplasia is mostly irreversible. If the progesterone is below 10ng/ml, it is almost impossible to save the embryo. It is also important to note that low progesterone is sometimes the cause of embryonic dysplasia, but more often it is the result of embryonic dysplasia. If there is a drop or disappearance of HCG before the location of the embryo is detected by ultrasound, it is usually a biochemical pregnancy as the saying goes. Those with biochemical pregnancy can no longer identify ectopic or intrauterine pregnancy. During regular blood draws for progesterone and blood HCG, if the rise in blood HCG is slow, monitor closely and check progesterone, blood HCG or ultrasound every 3 days or so. If an ectopic pregnancy is detected during this period, deal with it quickly. If intrauterine pregnancy has been confirmed, observe the development of the embryo in the uterus. If there is bleeding in the uterine cavity outside the fetal sac, the volume of bleeding is not large and can be observed with the possibility of absorption. If the blood progesterone is below 15ng/ml, the embryo is more dangerous. If the blood HCG continues to rise slowly with less than 20% rise in 3-day interval, it also indicates that the embryo is underdeveloped. When various indicators are combined to determine that the embryo has stopped developing, embryonic abortion should be cleared as soon as possible. If progesterone rises slowly, progesterone can be applied to preserve the fetus. Progesterone can make the endometrium more suitable for embryo development and inhibit uterine contraction to play a role in settling the fetus. Progesterone can be given orally, intramuscularly, or intravaginally. Commonly used methods: 1.Dydrogesterone tablets, 2 tablets orally in the morning and 2 tablets orally in the evening, 10mg each; 2.Progesterone pills, 2 pills orally in the morning and 2 pills orally in the evening, 100mg each; 3.Progesterone injection, 40mg intramuscularly once a day; 4.Progesterone extended-release gel, one vaginal gel daily. Progesterone dose should be adjusted by intermittent progesterone check during the medication period.