Effectiveness of pre-pregnancy lifestyle in preventing gestational diabetes mellitus—a systematic review and meta-analysis of 257,876 pregnancies

Background: Gestational diabetes mellitus (GDM) is hyperglycaemia first detected during pregnancy and affects about 1 in 6 live births globally, with a higher burden in LMICs. Objective: To determine the effectiveness of pre-pregnancy lifestyle in preventing GDM. Methods: Systematic searches of MEDLINE, Web of Science, Embase and CENTRAL identified RCTs, case-control, and cohort studies assessing pre-pregnancy diet and/or physical activity. Random-effects models estimated odds ratios (OR) with 95% CIs; risk of bias was assessed with Cochrane ROB-2 and Newcastle-Ottawa Scale. PROSPERO: CRD42020189574. Results: Of 7,935 records, 30 studies (257,876 pregnancies) were included. Meta-analysis of RCTs (N=5; n=2,471) showed a non-significant reduction in GDM risk (OR 0.76, 95% CI 0.50–1.17, p=0.21). Cohort studies showed that pre-pregnancy physical activity (N=4; n=23,263) was associated with lower GDM risk (OR 0.66, 95% CI 0.44–0.99, p=0.04), low carbohydrate/low sugar diet (N=4; n=25,739) was not statistically significant overall (OR 0.86, 95% CI 0.68–1.09, p=0.22), and higher quality diet scores (N=4) were protective (OR 0.72, 95% CI 0.60–0.87, p=0.0006). Conclusion: Some pre-pregnancy lifestyle components—diet/physical activity counseling, higher intakes of vegetables and fruits, low carbohydrate/low sugar patterns, higher quality diet scores, and higher physical activity—may reduce GDM risk. Evidence from RCTs and LMICs remains limited, underscoring the need for well-designed, personalized, multi-component pre-pregnancy RCTs to establish clinical and cost-effectiveness.

Swetha Sampathkumar, Durga Parkhi, Yonas Ghebremichael-Weldeselassie, Nithya Sukumar, Ponnusamy Saravanan