ABSTRACT
Five non-diabetic subjects, 5 gestational diabetics (GDM) treated with diet and 4 non-insulin dependent pregestational diabetics (NIDDM) treated with beef-pork insulin during their pregnancy, undergoing elective cesarean section (C-s), were given dextrose infusions without insulin for 7 hours (h) starting lh before the operation. Multiple blood samples were drawn up to 72 h after the C-s. The lowest glucose levels were observed at 3 3 or 6 h after surgery in all but two subjects. Plasma glucose below 2.75 mmol/l (49.5 mg/dl) were observed in 2 NIDDM patients. While in the non-diabetics and GDM the free (total) insulin and C-peptide values fell to very low levels, coinciding with the fall in plasma glucose, in the NIDDM there was a negative correlation between nadir glucose and free insulin levels with the progressive fall of antibody-bound insulin. In 3 out of NIDDM patients the antibodybound insulin fell to 57 to 73 per cent of the preoperative values. IGF-I/SmC, lower in the NIDDM, hGH immunoreactivity and hPL fell after C-s. The results suggest increased glucose utilization insulin-independent in the immediate postpartum in the non-diabetic pregnancy and GDM. However, in the NIDMM, in the presence of significant levels of free insulin, they tend to develop lower plasma glucose levels, sometimes hypoglycemia. Furthermore, lower IGF-I/Smc levels in the NIDDM in comparison to the non-diabetics and GDM would discard their role in the induction of hypoglycemia.