Taking emergency contraceptive pills to have a menstrual period the next month did not come may be pregnancy, menstrual disorders and other reasons. 1. pregnancy: emergency contraceptive pills can inhibit ovulation, change the shape of the uterine lining to play a contraceptive effect, but taking an emergency contraceptive pill, only one unprotected sex is effective. Eat emergency contraceptive pills after a period, the ovaries can resume ovulation, ovulation sex sperm and egg meet, can be pregnant. Estrogen and progesterone levels rise after pregnancy, leading to menopause. 2. Menstrual disorders: the main types of emergency contraceptive pills are estrogen-progestin preparations, anti-progestin preparations, and monoprogestin preparations. Emergency contraceptive pills have large hormone content and side effects, which can cause hypothalamic-pituitary-ovarian function axis dysfunction, endocrine disorders, leading to menopause. When taking emergency contraceptive pills causes menopause, consult a doctor in time to find out the cause of the disease under the guidance of the doctor and give appropriate treatment.