Metabolic phenotypes of early gestational diabetes mellitus and their association with adverse pregnancy outcomes.

Abstract

To describe the metabolic phenotypes of early gestational diabetes mellitus and their association with adverse pregnancy outcomes. We performed a post hoc analysis using data from the Vitamin D And Lifestyle Intervention for gestational diabetes prevention (DALI) trial conducted across nine European countries (2012-2014). In women with a BMI ≥29kg/m2 , insulin resistance and secretion were estimated from the oral glucose tolerance test values performed before 20weeks, using homeostatic model assessment of insulin resistance and Stumvoll first-phase indices, respectively. Women with early gestational diabetes, defined by the International Association of Diabetes and Pregnancy Study Groups criteria, were classified into three groups: GDM-R (above-median insulin resistance alone), GDM-S (below-median insulin secretion alone), and GDM-B (combination of both) and the few remaining women were excluded. Compared with women in the normal glucose tolerance group (n=651), women in the GDM-R group (n=143) had higher fasting and post-load glucose values and insulin levels, with a greater risk of having large-for-gestational age babies [adjusted odds ratio 3.30 (95% CI 1.50-7.50)] and caesarean section [adjusted odds ratio 2.30 (95% CI 1.20-4.40)]. Women in the GDM-S (n=37) and GDM-B (n=56) groups had comparable pregnancy outcomes with those in the normal glucose tolerance group. In overweight and obese women with early gestational diabetes, higher degree of insulin resistance alone was more likely to be associated with adverse pregnancy outcomes than lower insulin secretion alone or a combination of both.