Risk factors associated with fetal macrosomia were studied in 348 pregnancies resulting in the delivery of an infant weighing 4,000 g or more in a black population. Identifiable maternal risk factors included a mother in her 3rd decade of life, multiparity, maternal weight of 70 kg or more at the end of pregnancy, prolonged or post-term pregnancy, abnormal glucose tolerance and previous history of a macrosomic infant. Male infants had a higher risk of being macrosomic. Macrosomic infants accounted for 3.4% of all singleton deliveries, with their caesarean section rate of 33.9% being almost three times that of control infants. The importance of antenatal prediction of fetal weight is emphasised and suggestions for reduction of the high perinatal mortality and morbidity rates, as well as maternal morbidity, are discussed.