Progesterone injections generally have no effect on the fetus. Progesterone injection is a natural progesterone, which is mainly used to preserve fetus in pregnant women with pre-eclampsia and habitual miscarriage. Progesterone has important roles in maintaining metastatic endometrium, relaxing uterine smooth muscle, improving uterine blood supply and immune regulation in early pregnancy, and is widely used in clinical practice to prevent and treat miscarriage. However, progesterone injection must be used on time and according to the dose under the guidance of the doctor, otherwise it will affect the development of the fetus. The conventional dose is progesterone injection 20-40mg intramuscularly once a day, which has no effect on the fetus.