Authors : Finkelstein JL, Kurpad AV, Thomas T, Srinivasan K, Duggan C
Publication Year : 2017
BACKGROUND / OBJECTIVES:
Vitamin B12 deficiency during pregnancy has been associated with increased risk of adverse perinatal outcomes. However, few studies have investigated the burden and determinants of vitamin B12 status in young infants. This study was conducted to determine the associations between maternal and infant vitamin B12 status.
SUBJECTS / METHODS:
Pregnant women participating in a vitamin B12 supplementation trial in Bangalore, India, were randomized to receive vitamin B12 (50 µg) or placebo supplementation daily during pregnancy through 6 weeks postpartum. All women received 60 mg of iron and 500 µg of folic acid daily during pregnancy, as per standard of care. This prospective analysis was conducted to determine the associations between maternal vitamin B12 biomarkers (that is, plasma vitamin B12, methylmalonic acid (MMA) and tHcy) during each trimester with infant vitamin B12 status (n=77) at 6 weeks of age.
At baseline ( less than or equal to 14 weeks of gestation), 51% of mothers were vitamin B12 deficient (vitamin B12 less than 150 pmol/l); 44% of infants were vitamin B12 deficient at 6 weeks of age. After adjusting for vitamin B12 supplementation, higher vitamin B12 concentrations in each trimester were associated with increased infant vitamin B12 concentrations and lower risk of vitamin B12 deficiency in infants (P less than 0.05). After adjusting for vitamin B12 supplementation, infants born to women with vitamin B12 deficiency had a twofold greater risk of vitamin B12 deficiency (P less than 0.01). Higher maternal folate concentrations also predicted lower risk of vitamin B12 deficiency in infants (P less than 0.05). Impaired maternal vitamin B12 status, which combined both circulating and functional biomarkers, was the single best predictor of infant vitamin B12 status.
Impaired maternal vitamin B12 status throughout pregnancy predicted higher risk of vitamin B12 deficiency in infants, after adjusting for vitamin B12 supplementation. Future interventions are needed to improve vitamin B12 status periconceptionally, and to ensure optimal vitamin B12 status and health outcomes in pregnant women and their children.