Smoking During Early Pregnancy May Put Baby's Heart at Risk

WEDNESDAY, March 2 (HealthDay News) — Babies born to women who smoke in the first trimester of pregnancy are more likely to have a congenital heart defect than are the offspring of mothers who don’t smoke, a new study shows.

The increased risk ranged from 20 percent to 70 percent, varying by the type of defect. Detected heart defects included those that obstruct the flow of blood from the right side of the heart into the lungs, called right ventricular outflow tract obstructions, and openings between the upper chambers of the heart, known as atrial septal defects.

For the study, published Feb. 28 in Pediatrics, researchers from the U.S. Centers for Disease Control and Prevention analyzed data on 2,525 infants with congenital heart defects and 3,435 healthy infants born in Baltimore and Washington, D.C., from 1981 to 1989.

The findings of this and other studies suggest that eliminating smoking before or very early in pregnancy could prevent as many as 100 cases of right ventricular outflow tract obstructions and 700 cases of atrial septal defects each year in the United States, according to the CDC. For atrial septal defects alone, the agency said, that could save as much as $16 million a year in hospitals costs.

“Women who smoke and are thinking about becoming pregnant need to quit smoking and, if they’re already pregnant, they need to stop,” CDC Director Dr. Thomas R. Frieden said in an agency news release. “Quitting is the single most important thing a woman can do to improve her health as well as the health of her baby.”

Dr. Adolfo Correa, medical officer in the CDC’s National Center on Birth Defects and Developmental Disabilities, said that “successfully stopping smoking during pregnancy also lowers the chances of pregnancy complications such as preterm delivery and that an infant will have other complications such as low birth weight.”

Congenital heart defects, which impair heart function and can increase the risk of death or long-term disability, affect nearly 40,000 U.S. infants each year and contribute to about 30 percent of infant deaths caused by birth defects.

Each year in the United States, about 2,500 infants are born with right ventricular outflow tract obstructions and about 5,600 are born with atrial septal defects. In 2004, estimated U.S. hospital costs for all congenital heart defects totaled $1.4 billion, according to the CDC.

More information

The March of Dimes has more about congenital heart defects.