Shortening of menstrual period to 23 days is not necessarily menopause. It may be caused by uterine fibroids, luteal insufficiency, perimenopause or other reasons. 1. Uterine fibroids: Uterine fibroids can cause shortened menstrual cycle, increased menstrual flow and prolonged menstrual period due to poor contraction of the uterus, increased size of the uterine cavity and prolonged endometrial growth. 2. Luteal insufficiency: many reasons lead to the lack of follicular stimulating hormone in follicular phase, delayed follicular development, decreased estrogen level, thus leading to insufficient positive feedback of pituitary gland and hypothalamus; luteal insufficiency after ovulation, decreased progesterone; poor development of ovary itself, poor luteinization of granulosa cells after ovulation, insufficient secretion of progesterone, these pathogenesis can cause shortening of women’s menstrual cycle. 3. Perimenopause: During perimenopause, ovarian function declines and luteal insufficiency occurs, which can cause shortened menstrual cycles. In addition, there are other factors that can also lead to shortened menstrual cycles. It is recommended that the patient go to the hospital in time to identify the cause of the disease under the guidance of the doctor and give appropriate treatment.