At 12 weeks of pregnancy, the normal range value of progesterone should be more than 60nmol/L or 20ng/ml. Different medical units or different laboratory equipment used by different units are not the same, resulting in different normal ranges, and should be based on the local laboratory results as a reference. The value of progesterone some hospitals use nmol/L, some hospitals will use ng/ml, so the results of its normal range is also different. If the value of progesterone is low during pregnancy, pregnant women should carry out relevant examinations in time. If there is no fetal heartbeat or symptoms such as abdominal pain or vaginal bleeding, it is considered that there may be preterm miscarriage, which needs to be handled in time to preserve the fetus. If there is no such symptom, there is no need for special treatment, but should pay attention to rest, avoid exertion, supplement nutrition, especially pay attention to supplement folic acid, to prevent fetal neural tube deformity.