Mothers with low levels of vitamin B12 in their blood are at increased risk of having an infant with spina bifida - a birth defect in which the spinal cord fails to form properly, Dutch researchers report.

Based on previous research, pregnancy guidelines recommend that women consume enough folic acid to reduce the risk of spina bifida and related problems. The new findings suggest that these guidelines should also include recommendations about vitamin B12.

Dr. Regine P. M. Steegers-Theunissen, of University Medical Center Nijmegen, and colleagues report the findings in the American Journal of Obstetrics and Gynecology.

The 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 21 percent lower than those of other mothers. With the lowest levels, the risk of spina bifida was increased more than threefold.

“This study suggests that mothers with low vitamin B12 concentrations may benefit from the use of a…multivitamin supplement” around the time of conception, the researchers note. “However, this should be proved in future research.”

SOURCE: American Journal of Obstetrics and Gynecology, July 2004.