A normal woman’s menstrual period lasts for 2-7 days, and this range is normal. The amount of menstrual flow is generally around 30-50 ml, and greater than 80 ml is considered excessive. In other words, on the first day of menstruation, the amount of blood is particularly low, on the second and third days it is a little more, and after the fourth and fifth days it will gradually decrease. Some people’s menstrual flow is on the low side, which is only 2-3 days, while some people may have a high blood flow from the very beginning of their menstrual period, which lasts for 6-7 days, but their own hematopoietic function is strong, and they are not anemic even though their menstrual blood is a little bit too much.The range of 2-7 days is fine, and all of them belong to the normal range, and they don’t affect the pregnancy as long as their uterus has normal endometrial lining and ovulation is normal.