Division of Nutritional Sciences, Cornell University, Ithaca, NY, United States of America.
St. John's Research Institute, Bangalore, Karnataka, India.
PLoS One. 2021 Apr 6;16(4):e0248145. doi: 10.1371/journal.pone.0248145. eCollection 2021.
Vitamin B12 deficiency during pregnancy has been associated with adverse maternal and infant health outcomes. Few prospective studies have investigated vitamin B12 status early in pregnancy, and its links to infant vitamin B12 status, particularly in India where the burden of vitamin B12 deficiency is estimated to be the highest globally. The objective of this study was to examine the associations of maternal vitamin B12 biomarkers with neonatal vitamin B12 status.
Pregnant women (~12 weeks' gestation) were enrolled in a perinatal cohort study in Bangalore, India. Total vitamin B12, methylmalonic acid (MMA), and homocysteine concentrations were evaluated in maternal samples at enrollment and in neonates at birth using cord blood. Linear and binomial regression models were used to evaluate the associations of maternal vitamin B12 biomarkers with neonatal vitamin B12 status and perinatal outcomes.
A total of 63.2% of women had vitamin B12 deficiency (<148 pmol/L), 87.2% had vitamin B12 insufficiency (<221 pmol/L), and 47.3% had impaired vitamin B12 status (vitamin B12<148 pmol/L and MMA>0.26μmol/L) at enrollment; 40.8% of neonates had vitamin B12 deficiency, 65.6% were insufficiency, and 38.1% had impaired vitamin B12 status at birth. Higher maternal vitamin B12 concentrations at enrollment were associated with increased neonatal vitamin B12 concentrations (β(SE): 0.40 (0.05); p<0.0001) and lower risk of neonatal vitamin B12 deficiency (Risk Ratio [RR]: 0.53; 95% CI: [0.43, 0.65]; p<0.0001). Maternal vitamin B12 deficiency (RR: 1.97 [1.43, 2.71]; p<0.001), insufficiency (RR: 2.18 [1.23, 3.85]; p = 0.007), and impaired vitamin B12 status (RR: 1.49 [1.13, 1.97]; p = 0.005) predicted a two-fold increase in the risk of neonatal vitamin B12 deficiency at birth.
The prevalence of vitamin B12 deficiency was high early in pregnancy and predicted neonatal vitamin B12 status. Future research is needed to determine the role of vitamin B12 in the development of pregnancy and infant outcomes, and to inform screening and interventions to improve maternal and child health.
孕妇维生素 B12 缺乏与母婴健康不良结局有关。很少有前瞻性研究调查过妊娠早期的维生素 B12 状况，以及其与婴儿维生素 B12 状况的关系，特别是在全球估计维生素 B12 缺乏负担最重的印度。本研究的目的是研究母体维生素 B12 生物标志物与新生儿维生素 B12 状况之间的关系。
孕妇（约 12 周妊娠）在印度班加罗尔参加了一项围产期队列研究。在入组时和新生儿出生时使用脐带血评估母体样本中的总维生素 B12、甲基丙二酸（MMA）和同型半胱氨酸浓度。使用线性和二项式回归模型评估母体维生素 B12 生物标志物与新生儿维生素 B12 状况和围产期结局的关系。
共有 63.2%的女性存在维生素 B12 缺乏症（<148 pmol/L），87.2%存在维生素 B12 不足症（<221 pmol/L），47.3%存在维生素 B12 状态受损（维生素 B12<148 pmol/L 和 MMA>0.26μmol/L）；40.8%的新生儿存在维生素 B12 缺乏症，65.6%存在不足症，38.1%存在维生素 B12 状态受损。入组时母体维生素 B12 浓度较高与新生儿维生素 B12 浓度增加（β（SE）：0.40（0.05）；p<0.0001）和新生儿维生素 B12 缺乏症风险降低（风险比 [RR]：0.53；95%CI：[0.43，0.65]；p<0.0001）相关。母体维生素 B12 缺乏症（RR：1.97 [1.43，2.71]；p<0.001）、不足症（RR：2.18 [1.23，3.85]；p=0.007）和受损的维生素 B12 状态（RR：1.49 [1.13，1.97]；p=0.005）预测新生儿维生素 B12 缺乏症的风险增加两倍。
妊娠早期维生素 B12 缺乏症的患病率较高，可预测新生儿维生素 B12 状况。需要进一步研究以确定维生素 B12 在妊娠和婴儿结局发展中的作用，并为改善母婴健康提供筛查和干预措施。
