The study, published online May 21 in Pediatrics, found no difference in the incidence of all childhood cancers combined. But for two types, the difference was significant.
The incidence of primitive neuroectodermal tumors, a nervous system lesion, declined by 44 percent, while the incidence of Wilms tumor, a kidney cancer, declined by 20 percent.
The scientists acknowledge that no causal relationship can be inferred from the finding. Still, the lead author, Amy M. Linabery, a postdoctoral fellow at the University of Minnesota, said, "We feel that this is a positive message — folic acid fortification is not increasing rates of cancer."
She continued: "We've generated some new hypotheses, but we need follow-up studies."
Image: Pregnant woman with vitamins, via Shutterstock.