BackgroundThe consumption of dairy products in pregnancy is widely extended. However, whether the consumption of low or high fat dairy produce is more beneficial for maternofetal health has yet to be established.Research design and methodsThis prospective cohort study evaluated the effect of consumption of dairy products during pregnancy on the frequency of gestational diabetes mellitus (GDM) and a composite of adverse maternofetal outcomes (CMFO). Pregnant women receiving obstetric care between 2014 and 2017 were eligible. Those who consumed ≥3 servings/day of dairy products at 24–28 gestational weeks (GWs) were included and analyzed (n=2004). The population was stratified into three groups according to intake of fat-free dairy products—skimmed milk and fat-free yoghurt and cheese—(days/week): infrequent (1–2), average (3–6) and regular (7). Logistic regression analysis compared ORs (95% CI) for GDM and CMFO between the three groups (where the group of reference was the ‘infrequent’ intake group).ResultsAfter adjusting for confounding factors, no significant associations were found between the degree of consumption of fat-free dairy products and the risk of GDM and a CMFO. Moreover, when categorized by the degree of adherence to the Mediterranean diet (above or below the median score), associations were found between the ‘regular’ intake group and an increased risk of having a CMFO in women with a high adherence to the Mediterranean diet (OR: 1.50; 95% CI: 1.01 to 2.22; p<0.05). Weight gain during pregnancy did not differ among groups.ConclusionsThe consumption of fat-free dairy products during pregnancy does not seem to be beneficial for maternofetal health.