Researchers at Kathmandu Medical College explored whether providing vitamin B12 during pregnancy would affect infant neurodevelopment. The study, reported in a prominent medical journal, found no clear advantage in neurodevelopmental outcomes for babies whose mothers received B12 compared with those given a placebo.
Vitamin B12 supports nerve function and brain health. For generations, people have believed that maintaining adequate B12 levels during pregnancy and early infancy promotes healthier outcomes and stronger growth and development in babies.
The trial enrolled eight hundred pregnant women from Nepal, aged twenty to forty, who joined before the first 15 weeks of gestation. At baseline, a large share of participants, about seven hundred sixty-nine or roughly seventy-one percent, had B12 blood levels below the deficiency threshold. Participants were randomly assigned to two groups: one received fifty micrograms of vitamin B12 daily, and the other received a placebo.
Throughout the study, B12 supplementation successfully raised maternal vitamin B12 levels compared with placebo. Yet this biochemical change in the mothers did not translate into statistically significant differences in infant growth or neurodevelopmental indicators by the study’s end. The results align with World Health Organization guidance, which states that routine B12 supplementation during pregnancy is not required for all women. The findings contribute to ongoing evaluations of nutrition practices in pregnancy and support a cautious approach to adding supplements when there is no clear evidence of benefit.
In interpreting these findings, researchers note that several factors influence infant development, including genetics, overall maternal nutrition, and access to quality prenatal care. While correcting a deficiency during pregnancy remains important for maternal health, the study suggests that simply increasing B12 intake for all pregnant individuals may not yield measurable gains in early neurodevelopment for their children. This nuance highlights the value of targeted nutrition strategies that prioritize screening and individualized supplementation when specific needs are identified.
Historically, vitamin B12 requirements rise during pregnancy to support fetal development and maternal health. The Nepalese cohort studied here revealed that a substantial portion of expectant mothers began enrollment with suboptimal B12 status. By supplying B12 in a controlled trial, researchers could observe biochemical changes in the mother and monitor a range of potential infant outcomes, including motor milestones, cognitive indicators, and social development. While the primary neurodevelopmental metrics did not show a detectable advantage, the study provides a critical data point for policymakers and clinicians balancing potential benefits against costs and resource availability in prenatal care programs.
One takeaway is the importance of population specific nutrition policies. In regions where B12 deficiency is more prevalent, addressing this gap remains a public health priority. However, the research indicates that blanket supplementation during pregnancy should be reconsidered in favor of targeted approaches guided by routine screening and evidence of clear benefit for the mother or infant. For clinicians advising expectant families, the message is clear: maintaining balanced nutrition through a varied diet, appropriate prenatal vitamins when indicated, and careful monitoring of nutrient status remains the cornerstone of prenatal care. This approach helps ensure that interventions are effective and efficient, aligning with broader goals of maternal and child health in resource limited settings as well as more developed healthcare systems. Lancet study attribution.