Most women need supplementary iron in pregnancy, and in Britain are usually given it. More than half of all pregnant women may develop folic acid deficiency in the third trimester; this leads to megaloblastic anaemia in up to 3%. Since we last discussed the prophylactic use of iron and folic acid1 much more has become known about its effectiveness and safety, and many new preparations have been introduced for the purpose (see table). Their widespread use even in high dosage (5 mg or more daily) has apparently not caused neurological complications in undiagnosed Addisonian pernicious anaemia, as had been feared;2 3 nevertheless, great efforts have been made to determine the physiological requirement of folic acid in pregnancy, 4–6 to avoid any possibility of harming such patients.
Iron and Folic-acid Deficiency in Pregnancy
