What happened to the bleeding a few days ago?

A few days before menstruation bleeding, clinical diagnosis of menstrual cycle shortening. This situation is most common is ovarian corpus luteum function is not healthy, belongs to an endocrine disease. Ovarian ovulation after the formation of corpus luteum, corpus luteum continued to secrete progesterone and estrogen, maintain the endometrium, if not pregnant, corpus luteum gradually atrophied, estrogen and progesterone decreased, endometrial exfoliation bleeding, menstruation. If luteal function is not healthy, estrogen and progesterone are relatively low, often manifested as early menstruation or vaginal bleeding a few days before menstruation. After checking the progesterone on the 21st day of the menstrual cycle, progesterone can be clearly diagnosed. For luteal function is not healthy, progesterone supplementation is often given during the second half of the menstrual cycle.