Maternal obesity before pregnancy is associated with a higher risk for childhood cancer, particularly leukemia, but not with birth size, according to study results published in the American Journal of Epidemiology. Investigators also found a link between maternal weight gain and higher risk for neuroblastoma.
In a prospective cohort analysis, researchers used maternal and infant data to evaluate the link between trends in maternal weight before pregnancy and at delivery and the risk of developing any childhood cancer and leukemia. The mediation effect of newborn size on the association between maternal obesity and risk for childhood cancers was also studied.
All diagnoses of any cancer, and specifically of leukemia, were made by age 14 years in 2352 and 747, respectively, of the 1,827,875 infants included in the study. The risk for leukemia was 57% greater in children born to mothers with a body mass index ≥40.0 kg/m2 and 84% greater in neonates who weighed ≥30% than expected at birth.
Older maternal age was linked to an increased risk for any childhood cancer and leukemia, although no association between maternal height and gestational weight gain was found. In addition, nonwhite race was associated with lower risk.
“Future studies are warranted to elucidate the underlying biological mechanisms of early-life exposure through maternal obesity or manifestation of large or small infant size in the development of childhood cancer,” the authors noted. “Our findings, if confirmed by studies in other populations, would provide rationale for weight control of would-be mothers as a possible preventive measure against the risk of cancer in children.”
Stacy SL, Buchanich JM, Ma Z-Q. Maternal obesity, birth size, and risk of childhood cancer development. Am J Epidemiol. doi:10.1093/aje/kwz118