Association between healthy maternal dietary pattern and risk for gestational diabetes mellitus

Background/Objectives: Gestational diabetes mellitus (GDM) is associated with negative health effects for mother and child. The aim was to investigate the association between maternal dietary patterns and GDM. Subjects/Methods: Prospective observational study including 168 pregnant women aged 18–40 years, recruited at routine 20-week ultrasound. All participants kept a 4-day weighed food record following recruitment (commencement: gestational weeks 19–24). Principal component analysis was used to extract dietary patterns from 29 food groups. A Healthy Eating Index (HEI) was constructed. All women underwent an oral glucose tolerance test in weeks 23–28. Results: One clear dietary pattern (Eigenvalue 2.4) was extracted with positive factor loadings for seafood; eggs; vegetables; fruits and berries; vegetable oils; nuts and seeds; pasta; breakfast cereals; and coffee, tea and cocoa powder, and negative factor loadings for soft drinks and French fries. This pattern was labeled a prudent dietary pattern. Explained variance was 8.2%. The prevalence of GDM was 2.3% among women of normal weight before pregnancy ( n =86) and 18.3% among overweight/obese women ( n =82). The prudent dietary pattern was associated with lower risk of GDM (OR: 0.54; 95% CI: 0.30, 0.98). When adjusting for age, parity, prepregnancy weight, energy intake, weekly weight gain and total metabolic equivalent of task the association remained (OR: 0.36; 95% CI: 0.14, 0.94). Similar results were found when only including overweight or obese women (OR: 0.31; 95% CI: 0.13, 0.75). Conclusions: Adhering to a prudent dietary pattern in pregnancy was clearly associated with lower risk of GDM, especially among women already at higher risk because of overweight/obesity before pregnancy.