Progesterone levels are lower during the menstrual and follicular phases, and estrogen levels are higher. After ovulation, the estrogen level will drop rapidly, and the patient will have the formation of the corpus luteum, which secretes estrogen and progesterone, but mainly secretes progesterone, so the patient’s progesterone level will rise after ovulation, and it will reach the peak. It usually peaks one week before menstruation, so if you want to check the luteal function of the patient, it is usually recommended that the patient comes for progesterone check one week before menstruation. As long as the progesterone level can reach a certain peak, it proves that the patient’s luteal function is relatively good. The patient will usually have normal menstruation, or after pregnancy is not prone to habitual miscarriage or embryo stop developing due to insufficient luteal function.