(HealthDay News) — Maternal smoking in the first trimester is associated with increased risk of congenital heart defects (CHD), with a dose-dependent association observed, according to a study presented at the annual meeting of the Pediatric Academic Societies, held from May 3–6 in Vancouver, Canada.
Patrick M. Sullivan, MD, from the Seattle Children’s Hospital, and colleagues examined the correlation between maternal cigarette smoking during pregnancy and CHDs. Washington State birth certificate data were collected from 1989–2011. Maternal smoking status was compared during the first trimester of pregnancy among 14,128 cases and 62,274 randomly selected controls, matched by birth year.
The researchers found that the odds of being born with a CHD were increased for offspring of smoking mothers (odds ratio, 1.19). Specific correlations were seen for smoking and pulmonary valve anomalies, pulmonary artery anomalies, and isolated atrial septal defects (odds ratios, 1.53, 1.69, and 1.35, respectively). The correlation between maternal smoking and CHDs was dose-dependent (odds ratios for all subjects, 1.15, 1.25, and 1.56 for 1–10, 11–20, and >20 cigarettes/day, respectively), and was stronger for older mothers (35 years +; odds ratio for any smoking, 1.16) than for younger mothers (<35 years; odds ratio for any smoking, 1.61).
“Ongoing cigarette use during pregnancy is a serious problem that increases the risk of many adverse outcomes in newborns,” Sullivan said in a statement. “Our research provides strong support for the hypothesis that smoking while pregnant increases the risk of specific heart defects.”