Durable effects of implementation intentions: Reduced rates of confirmed pregnancy at 2 years.

Objective: To assess the long-term impact of implementation intention formation in reducing consultations for emergency contraception and pregnancy testing among teenage women. Design: Teenage women visiting a family planning clinic were randomly assigned to implementation intention versus control conditions. Main outcome measures: Objective measures of consultation outcomes were obtained from clinic records at 2-year follow-up (N = 227). Results: Rates of consultation for emergency contraception and pregnancy testing in the implementation intentions condition were 19% and 33% lower, respectively, compared to the rates observed in the control condition. Pregnancy rates were 43% lower. Intervention participants who consulted for emergency contraception and pregnancy testing at baseline were more than twice as likely to change to consulting for contraceptive supplies over the follow-up period compared to equivalent control participants (19% vs. 9%). Conclusion: The impact of implementation intention formation on reducing pregnancy risk among teenagers is durable over 2 years. Implementation intentions were successful in changing behavior among precisely those participants who were at greatest risk of becoming pregnant. (PsycINFO Database Record (c) 2011 APA, all rights reserved)