Twice a month? Is that normal?

Menstruation twice a month may be normal, menstrual cycle 21-35 days are normal. If calculated from the first day of the two menses, if the time between the two menses is 21 days, it is normal. For example, menstruation on the 1st and menstruation on the 22nd is normal. If the interval between two menses is shorter than 21 days, it belongs to too short menstrual cycle, which may be caused by endocrine imbalance, premature follicle development or no ovulation in the body. On the second to fifth days of menstruation, go to the hospital to detect thyroid hormone or sex hormone six tests to understand ovarian function, judge the condition according to the examination results, and carry out menstruation treatment. If a woman takes emergency contraception after sex, she has bleeding symptoms for 3-7 days. The second menstruation may be withdrawal bleeding caused by taking emergency contraception, which is a side effect of the drug.