Prenatal Smoking May Affect Newborn's Behavior
NEW YORK (Reuters Health) - Smoking during pregnancy appears to affect a newborn's behavior in ways similar to infants whose mothers used heroin or other illegal drugs, new study findings suggest.
Smoking between 6 and 7 cigarettes per day -- less than half a pack -- throughout pregnancy was associated with infants that were more excitable, less consolable and more rigid, according to the report published in the journal Pediatrics.
"The smoking effects in our study underscore the importance of smoking cessation programs, particularly for women of childbearing age," writes lead author Karen L. Law of Brown Medical School in Providence, Rhode Island.
Stacks of previous research show that women who smoke while pregnant are twice as likely to have a low-birth weight infant compared to their non-smoking peers. But, according to the new report, few studies have examined how prenatal cigarette exposure may affect an infant's behavior.
To investigate, the team of researchers evaluated the behavior of 27 infants born to mothers who reported that they smoked an average of 6 to 7 cigarettes a day during their pregnancy. Smoking habits were verified by measuring cotinine, a breakdown product of nicotine, found in the saliva. The babies were compared to 29 infants born to non-smoking mothers.
Babies born to mothers who smoked showed more signs of stress in their central nervous, gastrointestinal and visual systems, required more handling and were more rigid than other babies, the authors report.
The findings suggest the babies may have been undergoing nicotine withdrawal, they said.
What's more, Law's team reports that the levels of behavioral stresses that were observed were on par with those seen in infants born to mothers who use heroin and other opiate drugs, and the babies had stress behavior similar to those seen in preterm infants.
"The findings require us to take a step back," said Law in a prepared statement. "What are the Surgeon General warnings doing to stop smoking, given that the percentage of smokers is similar in the pregnant and general populations (about 18 percent and 25 percent respectively)? It is a huge public health concern that so many people are suffering the costs of smoking, including newborns."
SOURCE: Pediatrics 2003;111:1318-1323.