Level 1: Will having sex during menstruation cause pregnancy? Menstruation is an important stage in a woman’s menstrual cycle and one of the most fertile times for women. Therefore, many women worry about whether they will get pregnant if they have sex during their menstrual period. In fact, although the probability of pregnancy during menstrual intercourse is relatively low, there is still a certain risk. First, we need to understand the female menstrual cycle. Generally speaking, a woman\’s menstrual cycle lasts about 28 days, and the ovulation period is usually about 14 days before the start of menstruation. during ovulation