Smoking and oral contraceptive continuation

Background: Smoking may be related to early discontinuation of oral contraceptives (OC). Study design: This was a planned secondary analysis of a randomized clinical trial. Women aged less than 25 initiating OC at three inner-city publicly funded family planning clinics enrolled in the study. Subjects reported smoking status at enrollment; 3- and 6-month interviews assessed OC continuation. Results: One hundred eighty-nine (12%) of 1598 participants were current smokers. Smokers were more often lost to follow-up than nonsmokers (P<.01). Among participants with a 6-month interview, only 26% of smokers and 46% of nonsmokers were continuing OC (P<.001). After adjustment for confounding factors, smokers were still somewhat less likely to be continuing OC (adjusted OR 0.6, 95% CI 0.4-1.0). This association was unrelated to number of cigarettes smoked per day. Conclusions: These data suggest that young smokers may be more likely to discontinue OC within 6 months than nonsmokers. Smoking may be a marker for risk-taking behavior that extends to the premature discontinuation of OC.