Pre-Pregnancy Adherence to Mediterranean Diet and Risk of Gestational Diabetes Mellitus: A Prospective Cohort Study in Greece

Abstract

Gestational Diabetes Mellitus (GDM) is a growing epidemic affecting pregnant women and their offspring. This study aimed to identify the relationship between adherence to a Mediterranean diet (MD) before conception and the risk of GDM in a contemporary Greek pregnant cohort. A prospective cohort of pregnant women was recruited at the routine first trimester visit. Nutritional intake was evaluated using a population specific validated food frequency questionnaire (FFQ). Pre-pregnancy adherence to MD was derived using two different scoring systems, the Mediterranean diet index score (MDS), and a modified version. Adjusted odds ratios (aOR) were computed using multiple logistic regression models for each score derived. Of 743 participating women, 112 (15.1%) developed GDM. The MDS index showed that scoring 5-9 points (high adherence) was associated with a lower GDM incidence (aOR: 0.57 95% CI (0.32, 0.90), p = 0.02), while the modified MDS index showed no significant association for any level of adherence. Pre-pregnancy consumption of "meat and derivatives" and "fatty meat and processed meat" was associated with a higher risk of GDM, with both scoring systems (p = 0.008, p = 0.004, respectively). A higher adherence to a MD pre-pregnancy, especially with less meat consumption, may have a protective effect on the occurrence of GDM.

Keywords: GDM; Gestational Diabetes Mellitus; MD; Mediterranean diet; maternal nutrition; pregnancy.

Figure 1

Food group adherence for the two groups, GDM and no GDM, using the Mediterranean Diet Score (A) and the modified Mediterranean Diet Score (B), GDM: Gestational Diabetes Mellitus.

Figure 2

Mediterranean diet index score (A) and modified Mediterranean Diet Score (B) between the two groups, GDM: Gestational Diabetes Mellitus; MDS score: Mediterranean Diet Score. The main differences are highlighted in the red dotted ellipsoids, were the adherence of the non-GDM group is higher compared to the GDM group.