The secretion of progesterone is not constant, it is a kind of pulsatile secretion, so in about 40 days of pregnancy, as long as the progesterone is more than 25ng/mL then it means that the value of the progesterone is normal, sometimes when checking the progesterone will also drop, sometimes it will be down to 15ng/mL or so, if there is no abnormality and there is no bloodshed, it is not necessary to treat. However, if the progesterone is lower than 6ng/mL, it means that the progesterone is very low, and it is very difficult to get pregnant in this case. This means that the embryo may stop developing, or the phenomenon of pre-miscarriage may occur, and it is not very meaningful to keep the baby alive.