Effect of a Mediterranean Diet-Based Nutritional Intervention on the Risk of Developing Gestational Diabetes Mellitus and Other Maternal-Fetal Adverse Events in Hispanic Women Residents in Spain.

Gestational diabetes mellitus (GDM) is the most frequent morbidity found in pregnancy, and it increases the risk for several maternal-fetal complications. Hispanic women are considered at high risk. The St. Carlos GDM prevention study is a randomized controlled trial (RCT) conducted from 2016-2017. Normoglycemic women were randomized at 12-14 Gestation week (WG) to an intervention group (IG) receiving recommendations based on the MedDiet (supplemented with ExtraVirgin Olive Oil/pistachios), or to a control group (CG), recommended to limit fat intake. After RCT conclusion, IG recommendations were applied to a real-world group (RW) in routine clinical practice. The primary endpoint of the current study is an assessment of the GDM rate in Hispanic participants of the aforementioned studies: 132 RCT, 128 CT, 284 RW participants. The GDM rate was lower in IG: 19/128(14.8%), p = 0.021, and RW: 38/284(13.4%), p = 0.029) than in CG: 34/132(25.8%). Adjusted RR (95%CI) for GDM: 0.72 (0.50-0.97), p = 0.037 in IG and 0.77 (0.61-0.97), p = 0.008 in RW. Rates of urinary tract infections, emergency caesarean-sections and perineal trauma were also lower in IG and RW. Other adverse outcomes were lower in IG vs. CG. In conclusion, a MedDiet-based intervention reduces the rate of GDM and several adverse maternal-fetal outcomes in Hispanic women residing in Spain.