Vitamin D concentrations during pregnancy and in cord blood: a systematic review and meta-analysis

Abstract

Context Effect size estimates for the association between vitamin D concentrations in maternal blood during pregnancy and in cord blood vary widely across studies, but no meta-analysis has been conducted to ascertain this association. Objective The aim of this systematic review was to estimate the pooled effect size for the association between circulating 25-hydroxyvitamin D (25[OH]D) concentrations, a marker of vitamin D status, in maternal blood during pregnancy and in cord blood. Data Sources The PubMed, Embase, and Web of Science databases were searched from their inception to February 2021. Data Extraction Following the application of prespecified inclusion and exclusion criteria, 94 articles were eligible for full-text review, which was conducted by 2 authors independently. A third author was consulted when necessary and consensus reached. In total, 26 articles, which comprised 30 studies and 6212 mother-infant dyads, were included. Methodological quality was assessed using a modified version of the Joanna Briggs Institute’s Critical Appraisal Checklist for Studies Reporting Prevalence Data. Correlation coefficient (r) values for the association between maternal serum 25(OH)D concentrations during pregnancy and in cord blood were extracted. Data Analysis The r values were pooled using random-effects meta-analyses. Sensitivity and subgroup analyses were performed to investigate sources of heterogeneity. The pooled r for all studies was 0.72 (95%CI, 0.64–0.79), indicating high heterogeneity (I2 = 95%, P < 0.01). After influential and outlier studies were removed, the pooled r for 9 studies was 0.70 (95%CI, 0.66–0.74), which resulted in a substantial reduction in heterogeneity (I2 = 41%, P=0.10). Conclusion The findings support a positive and large correlation between maternal vitamin D concentrations during pregnancy and vitamin D concentrations in cord blood. Systematic Review Registration PROSPERO registration number CRD42021273348.

The Role of Maternal Vitamin D Deficiency in Offspring Obesity: A Narrative Review

“…Cord VD level is strongly linked with maternal VD status, especially that in the third trimester, as reported in a systematic review and meta-analysis (pooled r = 0.8, p < 0.001 during the third trimester vs. pooled r = 0.4, p = 0.01 before the third trimester) [ 60 ]. A RCT of VD supplementation in pregnancy (4400 IU/day vs. 400 IU/day) found that every 1 ng/mL increase in third trimester maternal 25(OH)D was associated with an increase in cord 25(OH)D of 0.43 ng/mL (1.1 nmol/L) (SE 0.05, p < 0.001) in the 4,400 IU/day group and of 0.30 ng/mL (0.8 nmol/L) (SE 0.06, p < 0.001) in the 400 IU/day group [ 61 ].…”

Association between vitamin D level and pediatric inflammatory bowel disease: A systematic review and meta-analysis

“…In the field of IBD research, it was found that vitamin D deficiency was associated with IBD ( 7 ). Vitamin D is a lipophilic compound synthesized in the skin under the sun, and it is hydroxylated to 25-hydroxyvitamin D [25(OH)D] in the liver and further hydroxylated in the kidneys to 1,25-dihydroxyvitamin D [1,25(OH)2D], which is the active metabolite ( 8 ). Some studies have shown that vitamin D protects the gut epithelial barrier by suppressing gut epithelial cell apoptosis ( 9 ), and other studies have shown that immunological dysregulation in IBD is characterized by epithelial damage ( 10 ).…”