Vitamin B12 status in term pregnant women and the cord blood samples of their newborns: A cross-sectional study.

In India, total vitamin B12 (Vit B12) and its active form (active B12) have not been studied in mother's blood and cord blood. We hypothesized that total and active B12 levels are sufficiently maintained in cord blood despite low levels in mothers. Two hundred term pregnant mother's blood and cord blood was collected and analyzed for total Vit B12 (radioimmunoassay method) and active B12 levels (enzyme-linked immunosorbent assay). Mean values of constant or continuous variables (hemoglobin (Hb), packed cell volume (PCV), mean corpuscular volume (MCV), white blood cells (WBC), and Vit B12) were compared in mother's blood and newborn cord blood using Student's -test and multiple comparisons within the groups were carried out with ANOVA. Spearman's correlation (Vit B12) and multivariable backward regression analyses (height, weight, education, body mass index (BMI) and Hb, PCV, MCV, WBC, and Vit B12 levels) were also performed. Total Vit 12 deficiency was highly prevalent at 89% and active B12 deficiency was 36.7% in mothers. Cord blood showed total Vit B12 deficiency prevalence of 53% and active B12 deficiency being 9.3%. Total Vit B12 (<0.001) and active B12 (<0.001) levels were significantly higher in cord blood when compared to mother's blood. In multivariate analysis, higher total and active B12 levels in mother's blood predicted higher levels of total and active B12 levels in cord blood. Our study showed higher prevalence of total and active Vit B12 deficiency in mothers compared to cord blood thus indicating their transfer to fetus irrespective of mother's status. Maternal Vit B12 levels affected cord blood Vit B12 levels.