Progesterone has a significant morphological effect on the endometrium stimulated by estrogen in the body and is essential for maintaining pregnancy. In the late menstrual period, it works together with estrogen to promote the development and proliferation of the endometrium, transforming it from the proliferative phase to the secretory phase, creating conditions for the implantation of the fertilized egg and the development of the embryo. It causes the entire endometrium to shed during the menstrual period. During pregnancy, it inhibits the movement of the uterus and its sensitivity to oxytocin, exerting an anti-abortion effect, and together with estrogen, promotes further development of the mammary glands, preparing for milk production. In large doses, it can through the feedback regulation of the hypothalamus-pituitary-anterior lobe-ovary axis inhibit the secretion of luteinizing hormone by the anterior pituitary gland, thereby inhibiting ovulation and achieving contraceptive effects. Progesterone can be used for habitual miscarriage, threatened miscarriage, uterine functional bleeding, menorrhagia, endometriosis, amenorrhea, ureteral calculi, benign prostatic hyperplasia, sleep apnea syndrome, and refractory ascites of liver cirrhosis.