Children whose mothers were overweight and smoked during pregnancy are at increased risk of being overweight, a new study has found.
The researchers also found that a high birth weight and rapid weight gain during the first year of life increase the risk of children being overweight.
The authors of the report reviewed 30 studies published between 1990 and 2011. The studies, which involved more than 200,000 people, tracked children’s health from birth until at least the age of 2 years.
Dr. Stephen Weng, of the U.K. Center for Tobacco Control Studies at the University of Nottingham, and colleagues said in a journal news release that, the analysis revealed several important and independent risk factors that increased children’s risk of being overweight. By itself, smoking during pregnancy increased the risk by nearly 48 percent, but this may be because smoking is a good indicator of mothers’ other social and lifestyle characteristics.
The investigators also found that breast-feeding and late weaning helped to reduce the chances of children being overweight. For example, breast-feeding cut the risk by 15 percent, the study authors noted in the news release.
There was no link between mother’s age, level of education, ethnicity or depression symptoms and children’s risk of being overweight. Evidence was inconclusive for type of delivery, weight gain during pregnancy, weight loss after pregnancy and whether a child was a fussy eater, the authors added.
"Several risk factors for both overweight and obesity in childhood are identifiable during infancy," Weng and colleagues concluded in the report. "Future research needs to focus on whether it is clinically feasible for health care professionals to identify infants at greatest risk."
Although the study found an association between certain maternal and early childhood factors and a child’s risk of being overweight, it did not prove a cause-and-effect relationship.
Archives of Disease in Childhood, news release, Oct. 29, 2012