Association between Dietary Diversity during Pregnancy and Gestational Diabetes Mellitus: A Prospective Cohort Study

The study aims to prospectively examine the association between the minimum dietary diversity for women (MDD-W) score and risk of gestational diabetes mellitus (GDM).

All participants were pregnant women enrolled in the Tongji Maternal and Child Health Cohort. Dietary intake was assessed using a food frequency questionnaire (FFQ) or 24-h dietary recall. The MDD-W score was constructed by categorizing all food items into 10 food groups, following the Food and Agriculture Organization guidelines. Oral glucose tolerance tests (OGTT) were conducted during 24-28 weeks of gestation to screen for GDM. Poisson regression models were used to assess the association between MDD-W scores and GDM risk.

In total, 357 (11.8%) of the 3,026 women were diagnosed with GDM. Compared with participants whose MDD-W score was ≥ 8, those with a score of 5-7 had an increased risk of GDM (relative risk ( RR): 1.32; 95% confidence interval ( CI): 1.03, 1.69), and those with a score ≤ 4 had a significantly higher GDM risk ( RR: 1.58; 95% CI: 1.12, 2.26). Furthermore, these findings indicate that pregnant women with MDD-W scores < 8, in conjunction with being overweight or obese before pregnancy and excessive gestational weight gain, have the highest risk of developing GDM.

These data suggest that a higher MDD-W score during pregnancy is independently associated with a lower GDM risk. Therefore, promoting dietary diversity and weight management is recommended to protect pregnant women from developing gestational diabetes.