By Robert Preidt
Researchers looked at test results for excessive protein in the urine (proteinuria) -- which is a sign of reduced kidney function -- in nearly 44,600 children in Japan who were followed until age 3.
Children of mothers who smoked during pregnancy were 1.24 times more likely to show signs of kidney damage than those whose mothers were nonsmokers, the investigators found.
Although the study found an association between smoking during pregnancy and kidney damage in children, it could not prove cause and effect.
"Maternal smoking during pregnancy is known to be associated with preterm birth, low birth weight, and [oxygen deficiency in newborns]. The findings from this study suggest an additional adverse effect of maternal smoking during pregnancy," said study leader Dr. Koji Kawakami. He is a professor and chairman of the department of pharmacoepidemiology at Kyoto University in Japan.
The study was published online Dec. 22 in the Clinical Journal of the American Society of Nephrology.
"Prevention of child proteinuria is important since child proteinuria can lead to development of chronic kidney disease in adulthood and, ultimately, end-stage [kidney] disease," Kawakami said in a journal news release.