In the 3rd month of pregnancy, if there are no abnormal symptoms such as disappearance of early pregnancy reaction, vaginal bleeding, lower abdominal pain, etc., there is no need to check progesterone. The development of the fetus in the 3rd month of pregnancy is basically stable, and the value of progesterone continues to rise during pregnancy, basically there will be no low progesterone value. However, it is necessary to do ultrasound to check whether the development of the embryo is normal or not, and check the progesterone again if necessary. If abnormal symptoms such as vaginal bleeding suddenly appear in the late stage, it is necessary to go to the hospital in time to check the value of the progesterone and other related tests, and follow the doctor’s instructions to take medication or injections to preserve the fetus, or other corresponding treatments. During pregnancy, you should pay attention to a reasonable diet, drink more water, supplement protein and nutrition, do not overwork and strenuous exercise, avoid staying up all night, otherwise it may affect the development of the fetus, or even cause miscarriage.