Trends in smoking before, during, and after pregnancy in ten states

While trends in smoking prevalence during pregnancy are known, little is known about trends in quitting during pregnancy and resuming smoking after pregnancy.

This study examined the trends in and correlates of quitting during pregnancy and resuming smoking after pregnancy.

We used population-based random surveys of recent mothers in ten U.S. states (total of 115,000 women) conducted between 1993 and 1999.

Although the prevalence of smoking 3 months before pregnancy was stable at around 26%, quitting during pregnancy rose from 37% to 46% between 1993 and 1999. Adjusted for maternal and state characteristics, the odds of quitting during pregnancy increased 51% between 1993 and 1999 (odds ratio [OR]=1.51; 95% confidence interval [CI]=1.08-2.12). Approximately half of the women who quit smoking during pregnancy resumed smoking within 6 months postpartum. Primiparous, privately insured, college-educated women are more likely to quit and least likely to resume smoking after delivery, compared to multiparous, Medicaid-insured, and high school-educated women. Teenaged women are more likely to quit, but also more likely to resume smoking than older women.

The increase in quit rates during pregnancy is encouraging, but the lack of any change in smoking before pregnancy or in postpartum relapse rates suggests that permanent changes in maternal smoking will require additional focus.