Detection and treatment of early gestational diabetes mellitus: a systematic review and meta-analysis of randomized controlled trials.

Abstract

Objective: To estimate the impact of detection and treatment of early gestational diabetes mellitus on short-term maternal, fetal, and neonatal outcomes. We defined 2 maternal (gestational diabetes prevalence and cesarean section) and 2 neonatal (preterm birth and macrosomia) primary outcomes. We also defined 5 maternal and 12 fetal-neonatal secondary outcomes.

Data sources: Ovid Medline, Cochrane CENTRAL, and Embase since inception. The search was updated in November 2024.

Study eligibility criteria: Inclusion criteria: randomized controlled trials addressing detection and treatment of early gestational diabetes (diagnosed before 20 completed weeks).

Exclusion criteria: pregestational diabetes or overt diabetes in pregnancy.

Study appraisal and synthesis methods: The Cochrane Handbook was used to guide data extraction and interpretation including risk of bias assessment (Risk of Bias 2 tool). Aggregation and comparison of results were performed with Revman 5.4.1. Pooled relative risk and mean differences were calculated with 95% confidence intervals using random-effects models. The quality of the evidence for primary outcomes was summarized using Grading of Recommendations Assessment, Development and Evaluation criteria.

Results: We identified 1221 unique references. Seven articles addressing early gestational diabetes met the eligibility criteria with a total of 30,791 participants. These studies used 2 strategies: (1) treatment vs usual care of women with a diagnosis of early gestational diabetes and (2) population-based approaches, either performing screening (vs not) or using different cutoffs for diagnosis. In studies comparing treatment vs usual care, differences were observed only in secondary outcomes: more drug treatment, less maternal weight gain, lower birthweight, and less respiratory distress. In studies comparing different population-based strategies, primary outcomes differed for a higher rate of early and overall gestational diabetes (relative risk, 5.50; 95% confidence interval, 3.56-8.48 and 1.83; 95% confidence interval, 1.41-2.38, respectively) and a lower rate of primary cesarean section (relative risk, 0.88; 95% confidence interval, 0.84-0.93); as to secondary outcomes, differences were observed in terms of higher total pregnancy-induced hypertension and preeclampsia. The quality of evidence for most outcomes was low/very low.

Conclusion: Detection and treatment of early gestational diabetes mellitus do not offer indisputable benefits either in treated women or at the population level. More studies are required to elucidate this issue.