This analysis reviews published studies of cord haemoglobin values in developing countries and compares findings for populations that are either exposed or not exposed to malaria. The review indicates: first, that fetal anaemia is common in women with chronic moderate-to-severe iron deficiency anaemia; second, that a severe degree of fetal anaemia is reported in several areas where malaria in pregnancy is common. Different levels of fetal anaemia or polycythaemia arise in relation to the duration and severity of maternal anaemia during pregnancy, but in malarious areas the fetal anaemia appears to be out of proportion to the level of maternal anaemia. Haemoglobinopathies are likely to play a contributory role in causing fetal anaemia. The concept is advanced that malaria may contribute to fetal anaemia as a result of immune haemolysis of sensitized red cells. Sensitization could be from malaria antibodies and antigens which cross the placenta. Further evidence is required to prove this hypothesis. The importance of fetal anaemia is that it is likely to relate to the pattern and risk of developing anaemia in infancy.