Conducted by experts at the University of North Carolina at Chapel Hill, the study has also found that single mothers or women lacking the social and financial resources to deal with being a new parent are more likely to relapse.
"In the future we can look at these and other factors in women who quit smoking during pregnancy to assess who is at low or high risk of relapse. We can then offer more intensive interventions for those at higher risk to address the physical, behavioral and social issues related to relapse," says Carol E. Ripley-Moffitt, research associate in UNC's department of family medicine, and the study's lead author.
She highlights the fact that smoking during pregnancy increases the risks of pregnancy complications, decreased birth weight and SIDS (Sudden Infant Death Syndrome).
She also says that the past 15 years have seen a steady decrease in the number of women who smoke while pregnant, in part because of an overall decline in smoking rates among all women of childbearing age, and in part because of interventions targeting women during the prenatal period.
"But more needs to be done because over 50 percent of women who quit the habit during pregnancy are smoking again at six months postpartum," she says.
Carol claims that her study is the first to examine not only the factors leading to relapse, but also those leading to a smoke-free life after pregnancy.
For their study, she and her colleagues interviewed 94 pregnant women attending prenatal clinics in central North Carolina, who had quit smoking before 30 weeks gestation.
The women were questioned about their decision to quit during pregnancy, how they quit, and what they would do in the future.
While 43 subjects remained smoke-free, 51 had relapsed when interviewed at 4 months postpartum.
Women who had remained smoke-free were asked about the benefits they had experienced, how they would handle temptations to smoke, how they had rewarded themselves for not smoking, and what support they might need to remain smoke-free.
Women who had relapsed were asked to describe specific situations that caused them to return to smoking, their feelings about smoking again, perceptions about the dangers of second-hand smoke, and what would need to be different in their lives in order to stop smoking again.
The researchers found that women who remained smoke-free after giving birth were bolstered by strong social support, strong internal belief systems, strong beliefs in postpartum health benefits of not smoking, negative experiences with a return to smoking and concrete strategies for dealing with temptations.
On the other hand, women who relapsed were undermined by easy access to cigarettes, reliance on cigarettes to deal with stress, lack of financial resources, lack of resources for childrearing, and low self-esteem.
Carol thinks that her team's findings may be useful for clinicians to distinguish between pregnant women who will ultimately relapse from those that will remain smoke free after giving birth.
She says that the findings also suggest that any new programs aimed at improving quit rates must be comprehensive in nature - they must give women the tools to acquire new skills, deal with addiction and improve life circumstances, socially and financially.
"Many of the women who relapsed were already trying to quit again when we interviewed them. While there is no simple solution, we recommend directly addressing the social and financial stresses that lead to relapse. We hope that our study will encourage creative interventions to help mothers sustain a smoke-free lifestyle after pregnancy, improving overall health for women and their families," she says.
The study has been published in the journal Nicotine and Tobacco Research.