"This current study suggests another possible protective effect for the vitamins," said study leader Greta R. Bunin, Ph.D., of The Children's Hospital of Philadelphia. She added, "Children whose mothers took multivitamins close to the time of conception seemed less likely to suffer medulloblastoma and primitive neuroectodermal tumours of the brain."
Bunin led a study comparing 315 children diagnosed with those tumours before age six to 315 randomly chosen healthy children. The children with cancer, all of whom were diagnosed between 1991 and 1997, were registered in the Children's Oncology Group, a multicenter collaborative organisation of paediatric cancer programs in the U.S. and Canada.
The researchers questioned the mothers in a telephone survey. The protective effect of the multivitamins taken early in pregnancy was weakly significant, but because it was similar to previous, more statistically significant findings by Bunin's team in 1993, the authors conclude the apparent benefit is unlikely to have occurred by chance.
The researchers found that taking multivitamins later in pregnancy did not significantly reduce the child's risk of medulloblastoma. "Our findings suggest that the time close to conception may be a critical period in the development of these tumours," said Bunin.
In terms of a possible risk factor, the researchers also questioned mothers about how frequently they ate cured meats, such as ham, hot dogs, lunch meat, sausages and smoked fish. Although those foods contain compounds shown to cause nervous system tumours in animals, Bunin's team found no increased risk of brain tumours in children whose mothers frequently ate those meats while pregnant. "Taking multivitamins in the first few weeks of pregnancy definitely helps prevent neural tube defects," concluded Bunin. "While more research remains to be done, our findings suggest that multivitamins may prevent some brain tumours as well."
MEDICA.de; Source: Children's Hospital of Philadelphia