Tropical obstetrics and gynaecology. 1. Anaemia in pregnancy in tropical Africa

Major causes of anaemia in pregnancy in tropical Africa are malaria, iron deficiency, folate deficiency and haemoglobinopathies: now there is added also the acquired immune deficiency syndrome (AIDS). Anaemia is often multifactorial, with the different causes interacting in a vicious cycle of depressed immunity, infection and malnutrition. Anaemia progresses through 3 stages: compensation, with breathlessness on exertion only; decompensation, with breathlessness at rest and haemoglobin (Hb) below about 70 g/litre; cardiac failure, with Hb below about 40 g/litre. Without treatment, over half of the women with haematocrit less than 0.13 and heart failure die. Maternal anaemia, malaria and deficiencies of iron and folate cause intrauterine growth retardation, premature delivery and, when severe, perinatal mortality. Surviving infants have low birthweights, immune deficiency and poor reserves of iron and folate. They have entered already the vicious cycle of infection, malnutrition and impaired immunity. Treatment with blood transfusions is even more hazardous since the advent of AIDS, and should be limited to saving the life of the mother. Treatment of malaria is complex as chloroquine-resistant strains are now common. Prevention remains relatively easy with proguanil and supplements of iron and folic acid and is highly cost-effective in the improvement of maternal and infant health; it is more important than ever as it avoids the unnecessary exposure of women and infants to HIV transmitted through blood transfusion.