Association Between Plant-Based Dietary Indices and Mediterranean Diet Score With the Odds of Gestational Diabetes Mellitus in Iranian Women: A Case-Control Study.

INTRODUCTION

Gestational diabetes mellitus (GDM) is a significant pregnancy complication. This study aimed to assess the association between plant-based dietary indices (PDI) and the Mediterranean Diet Score (MDS) with the odds of GDM in Iranian women.

METHODS

A case-control study was conducted involving 276 pregnant women (138 with GDM and 138 controls). Dietary intake was assessed using a validated food frequency questionnaire to calculate MDS, healthy PDI (hPDI), and unhealthy PDI (uPDI). Multivariable logistic regression was used to determine associations.

RESULTS

Higher adherence to MDS (OR: 0.37; 95% CI: 0.18-0.73) and hPDI (OR: 0.41; 95% CI: 0.22-0.79) was associated with lower odds of GDM. Conversely, higher uPDI adherence was associated with increased odds of GDM (OR: 4.98; 95% CI: 2.39-9.34).

DISCUSSION: A Mediterranean diet or a healthy plant-based diet may reduce GDM risk, while an unhealthy plant-based diet may increase it, highlighting the importance of diet quality in GDM prevention.