The World Health Organization estimates that 58% of pregnant women in developing countries are anemic. In spite of the fact that most ministries of health in developing countries have policies to provide pregnant women with iron in a supplement form, maternal anemia prevalence has not declined significantly where large-scale programs have been evaluated. During the period 1991-98, the MotherCare Project and its partners conducted qualitative research to determine the major barriers and facilitators of iron supplementation programs for pregnant women in eight developing countries. Research results were used to develop pilot program strategies and interventions to reduce maternal anemia. Across-region results were examined and some differences were found but the similarity in the way women view anemia and react to taking iron tablets was more striking than differences encountered by region, country or ethnic group. While women frequently recognize symptoms of anemia, they do not know the clinical term for anemia. Half of women in all countries consider these symptoms to be a priority health concern that requires action and half do not. Those women who visit prenatal health services are often familiar with iron supplements, but commonly do not know why they are prescribed. Contrary to the belief that women stop taking iron tablets mainly due to negative side effects, only about one-third of women reported that they experienced negative side effects in these studies. During iron supplementation trials in five of the countries, only about one-tenth of the women stopped taking the tablets due to side effects. The major barrier to effective supplementation programs is inadequate supply. Additional barriers include inadequate counseling and distribution of iron tablets, difficult access and poor utilization of prenatal health care services, beliefs against consuming medications during pregnancy, and in most countries, fears that taking too much iron may cause too much blood or a big baby, making delivery more difficult. Facilitators include women's recognition of improved physical well being with the alleviation of symptoms of anemia, particularly fatigue, a better appetite, increased appreciation of benefits for the fetus, and subsequent increased demand for prevention and treatment of iron deficiency and anemia.