Maternal Obesity Ups Risk for Urinary Tract Birth Defects

(HealthDay News) — An obese woman is more likely to have a baby with kidney and urinary tract birth defects, new research suggests.

The findings are to be presented Nov. 14 at the annual meeting of the American Society of Nephrology (Kidney Week), held from Nov. 11 to 16 in Philadelphia.

For the study, the researchers looked at medical charts, including birth and hospital discharge records, from 2003 to 2012. They found 3,221 cases of kidney or urinary tract abnormalities and compared them with more than 13,000 newborns without the abnormalities.

Looking at pre-pregnancy weight records, the researchers found that mothers who delivered children with the birth defects were almost 1.3 times more likely to be obese than those whose infants did not have the kidney and urinary tract defects. 

Because the researchers went by hospital codes, they could not determine which defects were most common or how severe they were.

The mechanism behind the association isn’t known, lead researcher Ian Macumber, MD, a pediatric nephrology fellow at Seattle Children’s Hospital, told HealthDay. “There is certainly some question as to whether insulin may play a role in this,” he said.


  1. American Society of Nephrology Kidney Week; Nov. 11-16, 2014; Philadelphia.