[Small-for-age babies: etiological factors in the Cape colored population].

One hundred and thirty-one small-for-dates Cape Coloured newborns and their mothers were compared with 81 appropriately grown Cape Coloured newborns and their mothers in order to determine aetiological factors in intra-uterine growth retardation. The mothers of the small-for-dates babies differed from the control mothers in the following respects: their postpartum weight and weight for height were less, their placentas were lighter, their incomes were lower, they smoked more heavily, attended antenatal clinics less frequently, and their social conditions, educational status, dietary intake, weight gain during pregnancy and attitude towards pregnancy were inferior. Their previous babies weighed less than the previous babies of control mothers. The study mothers, however, had higher total serum protein, serum albumin and haematocrit levels, which can probably be explained by a smaller plasma volume expansion. The VDRL test on cord blood was more often positive in study babies, but the mean cord blood IgM level did not differ in study and control babies. It is concluded that socio-economic factors play a major role in the aetiology of small-for-dates babies in the Cape Coloured population. Controlled trials of dietary supplementation seem to be indicated in high-risk mothers in this population group.