Jan. 16, 2003
BY ANN QUIGLEY

More women are quitting smoking during pregnancy but smoking trends before and after pregnancy are less encouraging, according to a study of more than 100,000 women.

While U.S. smoking rates have generally declined over the last decade, little is known about the specifics of smoking rates among women before, during and after pregnancy. Most studies on this subject have been limited by small size, but not this one.

"By pooling data over time and across states, we constructed the largest population-based sample ever, with detailed information on smoking among women before, during and after pregnancy," says study author Gregory J. Colman, Ph.D., of the department of economics at Pace University and the National Bureau of Economic Research, both in New York City.

With study co-author Ted Joyce, Ph.D., of the economics department at the City University of New York's Baruch College and the National Bureau of Economic Research, Colman analyzed data on 115,000 women, collected by the Pregnancy Risk Assessment Monitoring System of the Centers for Disease Control and Prevention. The data was collected from 1993 to 1999 in 10 U.S. states.

The number of women who reported that they had quit smoking during pregnancy rose during the study period, from 37 percent to 46 percent. But the number of quitters before and after pregnancy did not change significantly. Almost 60 percent of the women who had quit smoking during pregnancy resumed the habit within six months after delivery.

Additional study findings isolated smoking behavior by group. For example, women who were black, giving birth for the first time, privately insured and college educated were more likely to quit and least likely to resume smoking after delivery than women who were white, not giving birth for the first time, Medicaid-insured and high school-educated, respectively. Also, teenagers were both more likely to quit and more likely to resume smoking after pregnancy than older women.

The higher quit rates Colman and Joyce found during pregnancy may reflect public health efforts since 1993 to publicize smoking's dangers to mothers and families, as well as the 32 percent increase in the cost of cigarettes between 1998 and 1999, according to the study.

"Publicity surrounding the recent tobacco settlement between 46 states and the tobacco companies, as well as lawsuits leading up to the settlement, may also have contributed to antismoking sentiment," Colman adds. The study results are published in the January issue of the American Journal of Preventive Medicine.

Colman and Joyce also acknowledge that the rise in reported quit rates during pregnancy may be less of a cause of celebration than it appears: More women may be lying about their smoking because of their awareness of the stigma attached to smoking during pregnancy.

"One speculation is that self-reported quit rates may have increased due to the increased stigma associated with prenatal smoking," Colman says. "There may be less stigma associated with smoking before pregnancy and after delivery, especially if the baby is healthy."

Colman and Joyce suggest additional public health efforts are needed to make a serious dent in maternal smoking rates.

"Targeting antismoking therapies at women who have quit during pregnancy may be an effective way to reduce the danger to infants and older children from second-hand smoke," Colman concludes.

This research was supported by a grant from the National Institute for Child Health and Human Development.

---Health Behavior News Service