Insulin secretion and insulin sensitivity in normal pregnancy and gestational diabetes mellitus

Abstract

The purpose of this study was to evaluate insulin sensitivity ,β-cell function and islet-cell-directed autoimmunity in pregnant women with normal glucose tolerance and gestational diabetes mellitus(GDM). A total of 21 women with normal glucose tolerance and 21 women with GDM were evaluated at 24-36 weeks' gestation. Insulin resistance and β-cell function were evaluated using the continuous infusionof glucose with model assessment (CIGMA) method ,which aims to give a near-physiological stimulus and to evaluate the endogenous insulin and glucose response. Islet-cell autoantibody was positive in onewoman with GDM ,and glutamic acid decarboxylase autoantibodies were negative in both groups. The calculated CIGMA insulin resistance (CIGMA IR) was 2.04 ± 1.74 and 1.08 ± 1.22 in patientswith GDM and in control subjects ,respectively (p < 0.05). CIGMA percentage β-cell values were 64.04 ± 44.55% and 87.07 ± 52.77% in patients with GDM and control subjects ,respectively(p > 0.05). Decreased insulin sensitivity in late pregnancy was more evident in lean GDM subjects with mild hyperglycemia who did not require insulin therapy ,and β-cell function was partially preservedin this group of patients.