Progesterone is a progesterone drug, mainly used for preeclampsia, habitual abortion, anovulatory dysmenorrhea and amenorrhea. The symptoms of stomach discomfort after taking the medicine for three days may be caused by uterine contraction, menstruation, gynecological inflammation, etc. The causes are different, and different treatments should be used to find out the causes of the disease and carry out the corresponding treatment. 1. Uterine contraction: Progesterone is used in the treatment of preterm miscarriage to protect the fetus, the patient’s stomach is uncomfortable three days after taking progesterone, it may be caused by uterine contraction, which may be accompanied by vaginal bleeding. Further ultrasound examination is needed, as well as attention to bed rest, strengthen nutrition, if the abdominal pain is obvious and the bleeding is heavy, the doctor may need to determine whether to terminate the pregnancy. 2. The onset of menstruation: When progesterone is used in the treatment of anovulatory dysmenorrhea and amenorrhea, it will cause the endometrium to shed, resulting in the onset of menstruation, which may lead to stomach discomfort. Generally no special treatment, usually need to pay attention to abdominal warmth, can also use hot water bags for hot compresses. 3. Gynecological inflammation: If the patient has pelvic inflammatory disease, endometritis and other gynecological diseases, it can also lead to stomach discomfort. Ultrasound examination is needed to confirm the diagnosis of the disease, and follow the doctor’s instructions for treatment. Progesterone is a prescription drug, it is recommended that patients with discomfort, follow the doctor’s instructions to standardize the use of drugs, not blindly self-medication, in order to avoid serious effects.