Progesterone injections are effective in promoting the growth of endometrial glands, inhibiting smooth muscle contraction and favoring mammary gland development. It is a progesterone that enables the growth of endometrial glands, thickens the endometrium, and facilitates the implantation of fertilized eggs in the uterus soon after conception. Especially in the early stage of pregnancy, when the gestational sac has just implanted and is not stable enough to develop, it can ease the excitement and inhibit the contraction of the smooth muscle of the uterus so as not to cause abdominal pain, vaginal bleeding and other preterm abortions. After pregnancy, the development of the fetus is judged by testing the level of progesterone. If the value is significantly low, which is unfavorable to the development of the fetus, progesterone is used for fetal preservation treatment. It can promote the development of breast lobules and glands, facilitate the secretion of milk, and prepare for the breastfeeding of the baby after delivery.