If a woman has a normal menstrual cycle, ovulation usually starts on the 14th day after the start of menstruation. When menstruation has just arrived, it will not lead to the production of follicles and cause pregnancy due to the state of hormonal secretion in the body, but such cases require attention to local hygiene, which may cause gynecological inflammatory infections during menstruation and infections in the male genitourinary tract. Therefore, if you find your period after intercourse, it is generally not a cause of pregnancy. However, it is necessary to pay attention to whether it is the normal time of menstruation, some of them are caused by the bleeding of the uterus or irregular menstruation, which may cause a small chance of pregnancy if it is during ovulation.