The connection between low folic acid levels and birth defects is well known. Folic acid has been a mainstay in maternal nutrition, both to prevent spina bifida (a birth defect in which the spinal cord does not form properly) and to help with fetal development. Dutch researchers now report a similar connection between low B12 levels and birth defects. Folic acid and vitamin B12 act similarly in the body. Mothers with low levels of vitamin B12 in their blood also have an increased risk of having an infant with spina bifida.

According to a report in the American Journal of Obstetrics and Gynecology (July, 2004), researchers measured vitamin B12 levels in blood samples from 45 mothers and their children with spina bifida and from 83 mothers and their healthy children. Mothers of children with spina bifida had vitamin B12 levels that were more than 20% lower than those of mothers with children who were free of the defect. With the lowest B12 levels, the risk of spina bifida was increased more than 300%.

This study suggests that mothers with low vitamin B12 concentrations may benefit from the use of a multivitamin supplement. Because the neural tube forms early, supplementation should ideally begin at the time of conception according to the researchers. They do, however caution that this should be proven in future research.