Progesterone injection is usually 10-20mg intramuscularly daily or every other day. It is mainly used to treat preterm abortion and is indicated for luteal insufficiency, which is usually treated for two weeks after supplementation. If the vaginal bleeding stops and the ultrasound indicates that the embryo is alive, the pregnancy can continue. If the symptoms worsen, the ultrasound indicates embryonic dysplasia, and the human chorionic gonadotropin continues to fail to rise or fall, the presence of inevitable miscarriage needs to be considered and the pregnancy should be terminated. Luteal insufficiency is prone to miscarriage and requires bed rest, prohibition of sexual intercourse and, if necessary, sedation. Pay attention to keep the local cleanliness and hygiene to avoid the possibility of infection.