Early insulin response in latent gestational diabetes.

The intravenous glucose tolerance and glucose-stimulated early insulin response (EIR) were studied in late pregnancy and post partum in a reference (R) group of 9 women and in 18 women with latent gestational diabetes (LD), defined as a k-value of < 0.66/h and a normal fasting blood glucose concentration. During pregnancy, the LD group showed a lower EIR than the R group. However, the response ranged between normal and non-detectable. In the non-pregnant state, the EIR was the same in the two groups. The inability to increase the EIR during pregnancy wss most evident in women who even post partum had an abnormal glucose tolerance. In some women in the LD group, the EIR during pregnancy was even lower than in the non-pregnant state. The magnitude of the response in the non-pregnant state was not decisive of the capacity to increase the secretion during pregnancy. None of the women in the LD group developed manifest diabetes during pregnancy. They gave birth to children with normal birth weight, and no neonatal problems were registered except for one child with congenital heart malformation.