Maternal mid-pregnancy dietary patterns and inflammatory bowel disease in offspring from a prospective cohort study

Maternal diet during pregnancy may shape the child's immune system and gut microbiota maturation, potentially influencing the risk of developing inflammatory bowel disease (IBD). Therefore, we examined maternal a posteriori dietary patterns during pregnancy and their associations with pediatric-onset IBD risk in offspring.

The study comprised mother-child pairs from the Danish National Birth Cohort, which is a nationwide cohort of Danish pregnant mothers and their children, enrolled in 1996-2002 and followed prospectively through national health registers. Maternal dietary patterns during pregnancy were identified using k-means cluster analysis of 37 food group intakes, assessed with a food frequency questionnaire in gestational week 25 (second trimester). Pediatric-onset IBD cases (diagnosed at ≤18 years) were identified in Danish health registers. Cox regression explored associations between maternal dietary patterns during pregnancy and risk of pediatric-onset IBD in offspring, using the most common dietary pattern as reference.

Based on analysis of 56,097 mother-child pairs, of which 161 (0.29%) offspring developed pediatric-onset IBD, we identify five distinct maternal dietary patterns: diverse (n = 8388), non-recommended (n = 14,110), Mediterranean (n = 14,700), animal-based (n = 3808), and Western (n = 15,091). Notably, a diverse dietary pattern, characterized by high intakes of most food groups, is associated with 45% lower risk of pediatric-onset IBD in offspring compared to a Western pattern (hazard ratio: 0.55; 95% confidence interval: 0.31-0.97). No significant associations are observed for the other patterns.

This large prospective cohort study shows that maternal adherence to a diverse dietary pattern during pregnancy may contribute to lower risk of pediatric-onset IBD in offspring.