Efficacy of telephone counseling for pregnant smokers: a randomized controlled trial

Abstract

Objective: Reducing tobacco use in pregnancy is a public health priority. Brief smoking counseling during prenatal care is effective but generates modest cessation rates. Telephone counseling is an effective smoking cessation method that could offer pregnant women convenient access to more intensive smoking cessation counseling.

Methods: The efficacy of proactive pregnancy-tailored telephone counseling for smoking cessation was compared with a "best-practice" brief-counseling control in a randomized controlled trial of 442 pregnant smokers referred by prenatal providers and a managed care plan. Trained counselors using cognitive-behavioral and motivational interviewing methods called intervention subjects throughout pregnancy and for 2 months postpartum (mean = 5 calls, mean total contact = 68 minutes). Controls received one 5-minute counseling call.

Results: Cotinine-validated 7-day tobacco abstinence rates in intervention and control groups were 10.0% and 7.5% at end of pregnancy (odds ratio [OR] 1.37, 95% confidence interval [CI] 0.69-2.70; number needed to treat = 40) and 6.7% versus 7.1% at 3 months postpartum (OR 0.93, 95% CI 0.44-1.99). The intervention increased end-of-pregnancy cessation rates among 201 light smokers (< 10 cigarettes/day at study enrollment) (intervention 19.1% versus control 8.4%; OR 2.58, 95% CI 1.1-6.1; number needed to treat = 9.3) and among 193 smokers who attempted to quit in pregnancy before enrollment (intervention 18.1% versus control 6.8%; OR 3.02, CI 1.15-7.94; number needed to treat = 8.8); 63% of the sample (n = 267) was in one of these subgroups.

Conclusion: Proactive pregnancy-tailored telephone counseling did not outperform a brief "best practice" intervention among pregnant smokers. The intervention had efficacy in light smokers and in women who had attempted cessation earlier in pregnancy. Future studies should confirm whether telephone counseling benefits these groups of pregnant smokers.

Clinical trial registration: ClinicalTrials.gov, #NCT00181909.

Level of evidence: I.