GLUCOSE TOLERANCE IN NEWBORN INFANTS OF HEALTHY MOTHERS: ITS RELATIONSHIP TO THE MOTHERS' INSULIN RESPONSE TO GLUCOSE INFUSION
ABSTRACT It has earlier been postulated that a low insulin response to a glucose infusion is characteristic for the prediabetic individual (Cerasi & Luft 1967c). There is also evidence that some infants of individuals with low insulin response might have a carbohydrate metabolism that is in some respects similar to that of newborn infants to diabetic mothers (Edström et al. 1974). In the present study 15 infants to low insulin responders (ILR) and 22 infants to high insulin responders (IHR) were subjected to an intravenous glucose load (IVGTT) at 2–24 h age. A significant difference in glucose tolerance was found between the groups, the mean k-value for the ILR being 1.39 ± 0.41 and that for the IHR 1.05 ± 0.09 (P < 0.05). No mothers were found to have a gestational diabetes (with the possible exception of one low insulin responders) but during late pregnancy the mean k-value at IVGTT in the low responders decreased from nonpregnant values (the mean difference being 0.41 ± 0.20, P < 0.025) while the high responders did not show a corresponding decrease (mean difference 0.12 ± 0.25, P > 0.05). No other differences between the groups of infants that could influence the k-value could be found apart from the mothers being low or high insulin responders. Our findings show that a low insulin response in the mothers might affect the glucose tolerance of the foetus even in the absence of continuous maternal hyperglycaemia in late pregnancy.