Maternal B-vitamin intake and B-vitamin supplementation during pregnancy in relation to neonatal congenital heart defects: a case-control study with propensity score matching.

Background/objectives: The effect of dietary folate intake or folic acid (FA) supplementation during pregnancy on neonatal congenital heart defects (CHDs) remains inconclusive. There are limited data about non-folate-B-vitamin intake and the risk of CHDs. Furthermore, few studies have investigated dietary B-vitamin intake and B-vitamin supplement use simultaneously in relation to the risk of CHDs. This study aimed to explore the associations between maternal folate, vitamin B6, and vitamin B12 intake (dietary intake, total intake from diet and supplements); B-vitamin supplement use during pregnancy; and the risk of CHDs using the propensity score matching (PSM) method.Methods: We conducted a case-control study and included 760 cases and 1600 controls in Shaanxi Province, China. Diet, supplement use and other information were collected through a questionnaire interview. By using the 1:2 ratio PSM method, 396 cases were matched with 792 controls. Conditional logistic regression was used to investigate the associations between maternal B-vitamin intake and supplement use during pregnancy and CHDs.Results: Higher maternal dietary and total intake of folate and vitamin B12 were associated with reduced risk of CHDs, and the tests for linear trend were significant. Compared with non-users, maternal FA + VB6 + VB12 containing supplement use during pregnancy (OR 0.61, 95%CI 0.40-0.94), FA supplement use during pregnancy (OR 0.70, 95%CI 0.50-0.98) and in the first trimester (OR 0.62, 95%CI 0.46-0.85) were associated with a lower risk of CHDs.Conclusions: The findings of this study suggest that a higher intake of folate and vitamin B12 during pregnancy reduces the risk of CHDs. [ABSTRACT FROM AUTHOR]