You should not take progesterone capsules during menstruation. Progesterone capsules are a progestogen that can be used both to regulate the menstrual cycle and for fetal retention treatment. Taking progesterone capsules during menstruation can cause a decrease in the amount of menstruation and may even cause it to stop. Therefore, it is not necessary to take progesterone capsules if the menstrual flow is normal during normal menstruation. However, for abnormal uterine bleeding, progesterone can also be used to adjust the menstrual cycle, and progesterone can be taken orally to stop the bleeding when bleeding is occurring. However, to adjust the menstrual cycle or stop bleeding with progesterone, an ultrasound should be performed to check the condition of the uterine adnexa and the endometrium. A routine blood test should be performed to find out if the blood is anemic. If the hematocrit is less than 8g, it is recommended to use high potency progestin instead of progesterone to stop the bleeding, and to extend the duration of the medication until the anemia is corrected, then stop the medication and regularize the menstruation.