Prevalence and pregnancy outcomes of gestational diabetes mellitus by different international diagnostic criteria: a prospective cohort study in Vietnam.

Background: Several diagnostic criteria for gestational diabetes mellitus (GDM) have been developed and used internationally. This study estimated the prevalence of GDM and pregnancy outcomes among Vietnamese women.Methods: A prospective cohort study of 2030 women was undertaken in Vietnam between 2015 and 2016. Baseline interview and a single-step 75-g oral glucose tolerance test (OGTT) were conducted at 24-28 weeks of gestation. GDM was defined by five international diagnostic criteria: America Diabetes Association (ADA), European Association for the Study of Diabetes (EASD), International Association of the Diabetes and Pregnancy study groups (IADPSG), National Institute of Health and Clinical Excellence (NICE), and World Health Organization (WHO). Maternal and neonatal outcomes were assessed using medical records. Besides descriptive statistics and univariate analyses, logistic regressions were performed to ascertain the associations between GDM and maternal and neonatal outcomes.Results: The prevalence of GDM varied considerably by the diagnostic criteria: 6.4% (ADA), 7.9% (EASD), 22.8% (IADPSG/WHO), and 24.2% (NICE). Women with GDM according to EASD were more likely to have macrosomic infants (adjusted odds ratio (OR) 4.35, 95% confidence interval [CI]: 1.49-12.72), despite no apparent increase in risk under other criteria. Babies born to mothers with GDM appeared to be large-for-gestational age (LGA) by ADA criteria (adjusted OR 2.10, 95% CI: 1.10-4.02) or EASD criteria (adjusted OR 2.15, 95% CI: 1.16-3.98), when compared to their counterparts in the normal group. No significant differences in maternal and other neonatal outcomes were found between the normal and GDM groups.Conclusions: A global guideline is needed for the diagnosis, prevention and management of GDM.