5 menstruating symptoms that are very dangerous 1. Prolonged menstruation Women menstruate only 2 to 3 tablespoons of blood per month. If a woman menstruates more than 5 spoons it is a sign that something is not going well. Abnormal bleeding can cause anemia, since iron is lost when there is too much bleeding. These can be some causes of excessive bleeding: Uterine fibroids Instant abortion Changing contraceptive pills Uterine cancer Coagulation Disorders Use of…"5 menstruating symptoms that are very dangerous"