To appear in: Contraception

Abstract word count: 248 Manuscript word count: 2,500 Keywords: contraception; coitus interruptus; dual use Running title: Contraceptive strategies involving withdrawal Abstract Objective: Research assessing contraceptive use often focuses on most effective method used and suggests that very few women rely on withdrawal. We adopted a new measurement strategy in an attempt to measure contraceptive practices, and withdrawal in particular. Study Design: We collected data from a national sample of 4,634 U.S. women aged 18-39; the survey was administered online in November and December 2012. We obtained information about recent use of hormonal methods and coital methods using two separate items, and we placed withdrawal first on the list of coital methods. The analysis examines several measures of withdrawal use in the last 30 days: most effective method used, any use, use with other methods and withdrawal "method mix." Results: Among women at risk of unintended pregnancy, 13% reported that withdrawal was the most effective method used in the last 30 days, but 33% had used withdrawal at least once. Most women who used withdrawal had also used a hormonal or long-acting method (13% of the sample) or condoms (11%) in the last 30 days, and a minority reported using only withdrawal (12%). Younger women, women in dating relationships and women strongly motivated to avoid pregnancy had some of the highest levels of "dual" use of withdrawal with condoms or highly effective methods. Conclusion: Many women and couples in our sample used withdrawal in combination, or rotation, with condoms and highly effective methods. Findings suggest that some people who use withdrawal may be more versus less vigilant about pregnancy prevention. Implications: Health care providers who discuss contraception should include withdrawal in these conversations. A substantial minority of individuals has used it recently, and many appear to be using it as a backup or secondary method. If dual use were more widespread, it could help reduce the incidence of unintended pregnancy