Blood glucose and glycosylated haemoglobin levels measured at delivery in 27 normal and 19 diabetic women were compared with those of the corresponding fetuses and their birthweights. In both groups, neonatal blood glucose levels were significantly higher (p much less than 0.001) than the maternal levels despite significantly lower (p much less than 0.001) glycosylated haemoglobin values in the neonates. In the control group, there was a significant correlation of maternal glycosylated haemoglobin with both cord glycosylated haemoglobin and birthweight ratio (p less than 0.01). The same was not obtained in the diabetic group, suggesting a dissociation in glucose homeostasis between the diabetic pregnant mother and her fetus.