The act of intercourse does not usually cause a delay in the menstrual cycle, but if intercourse is unprotected and the woman becomes pregnant, menopause may occur in this case. Some women may experience a small amount of bleeding and think it is an irregular period. If a woman of normal childbearing age, who is sexually active and usually has regular periods, experiences symptoms such as delayed periods and abnormal menstrual flow after intercourse, pregnancy should be considered as a priority cause.