The duration of progesterone injection treatment varies depending on the situation. The use of progesterone for the treatment of functional uterine bleeding, generally use progesterone 10mg-20mg, daily intramuscular injection, a total of 3-5 days, can make the bleeding significantly reduced or stopped, after stopping the drug 2-3 days can have withdrawal bleeding. If progesterone is used for fertility preservation treatment, usually progesterone 20mg, daily intramuscular injection, has been injected until the vaginal bleeding stops after 3-7 days after stopping the drug, before stopping the drug need to gradually reduce the amount. During the treatment with progesterone, the value of progesterone should be rechecked regularly, and the development of the gestational sac should be observed at the same time. So how many days does progesterone need to be injected, each person’s situation is different, and the duration of treatment is also different.