Iron deficiency anemia can develop in women who have
unusually heavy periods (menorrhagia), because the blood loss can deplete iron
stores.
Menorrhagia is defined as losing more than
80 ml (2.7 fl oz) of blood per
month. It is the most common cause of iron deficiency anemia in women.
1
Any of the following characteristics may indicate abnormally heavy
menstruation:1
- Being unable to control blood flow with tampons
alone
- Requiring more than 4 pads per day or 12 pads per
period
- Passing blood clots:
- Larger than
2 cm (0.8 in) in
diameter
- Beyond the first day of the cycle
- Having a cycle that lasts longer than 7 days
Menstrual blood flow varies greatly from woman to woman. However, it
usually remains constant from one month to the next in the same woman. Certain
birth control intrauterine devices (IUDs) may increase blood flow. Use of oral
contraceptives often helps lighten blood flow and may decrease the risk of
iron deficiency anemia.