Menstrual blood loss and body iron stores in Brazilian women.

Menstrual blood loss (MBL) studies are relevant for developing world women as this could be an important cause of anemia. Whenever a contraceptive method is to be used by such women, consideration should be given to the method which least affects the volume of MBL. In 309 women considered as clinically healthy, MBL, serum ferritin, serum iron and hemoglobin levels were measured: a mean MBL of 23 ml was found. Age, weight, height and previous oral contraceptive use did not affect MBL. Higher parity women may have higher MBL levels but their hematologic indices are not altered. While body iron stores (as judged by serum ferritin levels) are depleted in women who bleed more than 60 ml per cycle, clinical anemia may not be present until their blood loss exceeds 80 ml per menstruation. Brazilian women who lose more than 60 ml of menstrual blood associated with multiple pregnancies without adequate iron supplementation may have a depletion of their body iron stores.