Purpose: This study aimed to explore effects of maternal folic acid (FA) supplementation during pregnancy on neurodevelopment in 1-month-old infants and to determine whether effects may be related to maternal circulating inflammatory cytokine concentrations.
Methods: This birth cohort study recruited 1186 mother-infant pairs in Tianjin, China, between July 2015 and July 2017. The women completed interviewer-administered questionnaires on their lifestyles and FA supplementation during pregnancy. Neurodevelopment was assessed in 1-month-old infants using a standard neuropsychological examination table. In 192 women, serum homocysteine (Hcy) and inflammatory cytokine concentrations were measured at 16-18 weeks of gestation.
Results: The infants whose mothers took FA supplements during pregnancy had a significantly higher development quotient (DQ) compared with those whose mothers were non-users (P < 0.05). After adjustment for maternal characteristics, supplementary FA use for 1-3 months, 3-6 months, and > 6 months were associated with the increases of 7.7, 11.0, and 7.4 units in the scale of infant DQ score compared with women reporting no supplement use, respectively (P < 0.05). FA supplementation was associated with a decreased serum concentration of Hcy (β = [Formula: see text] 0.19), which was correlated with women's serum inflammatory cytokine concentrations at 16-18 weeks of gestation (β = 0.57). Serum inflammatory cytokine concentrations were inversely related to DQ score in the 1-months-old offspring (β = [Formula: see text] 0.22).
Conclusions: Maternal FA supplementation during pregnancy favors neurodevelopment in the offspring at 1-month-old. This association may be mediated by changes in serum Hcy and inflammatory cytokine concentrations throughout pregnancy.
Keywords: Birth cohort study; Folic acid; Infant; Inflammatory cytokine; Neurodevelopment; Pregnancy.