what causes clotting during period
Uterine fibroid tumors can contribute to blood clots during a woman's menstrual period. A heavy flow is among the reasons for passing blood clots during a period. Birth control methods such as an intrauterine device (IUD) can cause a woman to pass blood clots during her period. Miscarriage can cause a woman to pass blood clots. Fibroid tumors that grow in the uterus can lead to blood clots during a period.