There is no necessary link between how long a period of low progesterone lasts and miscarriage. Low progesterone does not necessarily lead to miscarriage, some can recover on their own, and miscarriage can be avoided after active intervention. In early pregnancy, progesterone is mainly secreted by the corpus luteum of pregnancy, as pregnancy continues to progress to 8-10 weeks of pregnancy after the formation of the placenta, progesterone is mainly secreted by the placental syncytial trophoblast cells. There are many reasons for low progesterone. Under physiological circumstances, the progesterone secretion function of the corpus luteum of pregnancy is gradually replaced by the placenta from about 8 weeks of pregnancy, and progesterone may decline physiologically, but then it will rise again. In this case, continued observation is sufficient and does not necessarily lead to miscarriage. In addition, low progesterone can also occur in some pathological conditions, such as luteal insufficiency, embryonic dysplasia and ectopic pregnancy. Low progesterone due to luteal insufficiency and embryonic dysplasia can be supplemented to avoid miscarriage, while low progesterone due to ectopic pregnancy should be actively treated with surgery or medication. Therefore, low progesterone is not necessary to be too nervous, low progesterone is not necessarily related to abortion, should identify the cause of the close monitoring of fetal development and take targeted treatment.