For women who have a normal sexual life without contraception, if the period is delayed and does not come, the first thing to do in this case is to rule out the possibility of pregnancy. If you are not pregnant, then you can take further medication or injections to make your period come. Nowadays, if you stop taking progesterone injections after a few days, your period will come in 3-7 days after you stop taking them. This phenomenon is in the hormonal withdrawal bleeding and produces menstruation, but this is the case for women of childbearing age. If you are already pregnant, this injection will not work because progesterone has a fetus-preserving effect on women who are pregnant. In the case of women who have been menopausal for a long time and whose hormone levels are already low, progesterone injections will not produce a period either.