The normal range of progesterone in the second trimester is around 21-36ng/ml with some variability. If the progesterone value is too low, it will easily lead to vaginal bleeding and even the possibility of miscarriage, and monitoring of hormone levels in the blood is needed in early pregnancy. If the progesterone is too high, you need to be alert to gestational trophoblastic disease. Progesterone is a very important hormone to maintain a normal pregnancy and can reduce the probability of rejection by the body. The second trimester of pregnancy belongs to the early stages of pregnancy and requires special attention to prevent serious consequences. Pay attention to more rest, avoid overwork and staying up late, eat a reasonable and hygienic diet, pay attention to any abdominal pain and vaginal bleeding.