Differences in pregnancy outcomes and characteristics between insulin- and diet-treated women with gestational diabetes

Background Our aim was to evaluate the difference in pregnancy outcomes and characteristics between insulin- and diet-treated women with gestational diabetes (GDM). Methods Retrospective analysis of the medical files from 2010–2013 of women with GDM diagnosed with the Carpenter & Coustan criteria attending two clinics, one in a university and another in a non-university hospital. Characteristics associated with insulin use were analyzed. Multivariable logistic regression was used to adjust for confounders. For women attending the university hospital, indices of insulin sensitivity such as the reciprocal of the homeostasis model assessment of insulin resistance (1/HOMA-IR) and an index of beta-cell function, the Insulin Secretion-Sensitivity Index-2 (ISSI-2) were calculated. Results Over a 4 year period, 601 women were identified with GDM of whom 22.9 % were obese at first prenatal visit. 24.2 % needed insulin. Insulin did not prevent adverse outcomes, as women on insulin had higher rates of large-for-gestational age infants (LGA) (28.5 % vs. 13.1 %, p