Maternal and neonatal outcomes following the introduction of oral hypoglycaemic agents for gestational diabetes mellitus were comparable to insulin monotherapy in two historical cohorts.

Background: Gestational diabetes mellitus (GDM), a disorder of glucose intolerance first encountered during pregnancy, has far-reaching implications for both mother and child. Insulin therapy remains the 'gold standard' of care, with oral hypoglycaemic agents (OHAs) increasingly being viewed as potential alternatives.

Objectives: To compare maternal and neonatal outcomes in two cohorts of women with GDM exposed to either insulin monotherapy or OHAs.

Methods: A retrospective medical record review at Chris Hani Baragwanath Academic Hospital in South Africa was conducted for women with GDM diagnosed using the 100 g oral glucose tolerance test and/or random capillary blood glucose >11.1 mmol/L in 2010 - 2014. The findings were compared with a previous audit at the same clinic for the period 1992 - 2002. Variables of interest included maternal demographics, maternal comorbidities, glycaemic indices, treatments used during pregnancy, and obstetric and neonatal outcomes.

Results: A total of 192 women with GDM were identified for 2010 - 2014, and there were 348 women in the previous audit (1992 - 2002). Baseline characteristics and outcomes of women in the two cohorts were similar apart from earlier presentation (mean (standard deviation) gestational age (GA) 27 (7.5) weeks v. 28.3 (6.4) weeks; p=0.04), lower GA at delivery (36.3 (3.6) weeks v. 37 (1.6) weeks); p=0.008) and lower macrosomia rates (12.5% v. 4.9%; p=0.011) in the later cohort. When comparing the individual OHAs against insulin in the later cohort, both agents were comparable to insulin in terms of maternal and neonatal outcomes.

Conclusions: This study contributes to the paucity of data on the safety of OHAs in GDM pregnancy in terms of maternal and neonatal outcomes. OHAs were shown to be an effective alternative to insulin for women with GDM in whom lifestyle measures fail, particularly in a resource-poor setting.