Mothers’ exposure to second-hand smoke increases the risk of fetal heart defects, according to a new study published in the journal Environmental Pollution.
Researchers found that mothers in Guangdong, China exposed to second-hand smoke were 44% more likely—compared to mothers lacking exposure—to give birth to children with heart defects.
However, second-hand smoke was not the only risk factor for heart defects. Low household income, migrant status, and the father’s alcohol consumption all contributed to increased risk of fetal heart defects.
“Our findings were consistent with the hypothesis that low socioeconomic status is associated with a higher risk of fetal heart defects,” say the authors of the study.
To confirm fetal heart defects, physicians were consulted and their diagnoses were confirmed by a fetal heartbeat monitor. To determine smoke exposure and other information, participants were interviewed in-person.
Several previous studies—one published in 2010 in Lithuania, and one published in 2011 in Italy—had similar results. Both studies found increased risk of fetal heart defects in children with fathers who smoked.
The authors of the current study, and many others, claim that smoking is a significant public health concern in China.
With 300 million smokers—nearly the entire population of the U.S.—China is the world’s largest consumer of tobacco. Of those millions, a large majority are men. Only 2% of women are current smokers. These statistics, the researchers say, suggest that a large number of non-smoking females are exposed to second-hand smoke daily.
It is estimated, that among non-smokers in China, 73% are exposed to second-hand smoke every day.
“Our findings may help to identify high-risk populations for fetal heart defects,” the researchers say. “This provides an opportunity for targeted preventive interventions.”