The potential impact of iron supplementation during adolescence on iron status in pregnancy.

Iron deficiency anemia (IDA) during pregnancy is associated with significant morbidity for mothers and infants. Over 50% of pregnant women in developing countries suffer from IDA. It is also prevalent among adolescent girls because the growth spurt and onset of menstruation increase iron requirements. Women who conceive during or shortly after adolescence are likely to enter pregnancy with low or absent iron stores or IDA. Iron supplementation during adolescence is one of the new strategies advocated to improve iron balance in pregnancy. However, iron requirements are highest in the second and third trimesters and the model described here indicates that iron balance at this stage depends more on adequate intakes of bioavailable iron than on the size of the iron stores at conception. Furthermore, although supplementation will correct anemia and increase iron stores in girls, the positive effect on iron status will be temporary if their diets do not contain adequate bioavailable iron. Although iron status in early pregnancy may be improved if the period of supplementation continues up to the time of conception, supplementation before pregnancy should be viewed as an additional strategy to supplementation during the second and third trimesters.