OBJECTIVE: To estimate differences in continuation of oral contraceptive pills (OCPs) between U.S. resident women obtaining pills in U.S. family planning clinics compared with over-the-counter in Mexican pharmacies.
METHODS: In El Paso, Texas, we recruited 514 OCP users who obtained pills over the counter from a Mexican pharmacy and 532 who obtained OCPs by prescription from a family planning clinic in El Paso. A baseline interview was followed by three consecutive surveys over 9 months. We asked about date of last supply, number of pill packs obtained, how long they planned to continue use, and experience of side effects. Retention was 90%, with only 105 women lost to follow-up.
RESULTS: In a multivariable Cox proportional hazards model, discontinuation was higher for women who obtained pills in El Paso clinics compared with those who obtained their pills without a prescription in Mexico (hazard ratio 1.6, 95% confidence interval [CI] 1.1–2.3). Considering the number of pill packs dispensed to clinic users, discontinuation rates were higher (hazard ratio 1.8, 95% CI 1.2–2.7) for clinic users who received one to five pill packs. However, there was no difference in discontinuation between clinic users receiving six or more pill packs and users obtaining pills without a prescription.
CONCLUSION: Results suggest providing OCP users with more pill packs and removing the prescription requirement would lead to increased continuation.
LEVEL OF EVIDENCE: II
Continuation of oral contraception is higher among U.S. resident women obtaining pills over the counter in Mexico compared with those obtaining pills by prescription in the United States.
From the Population Research Center, University of Texas at Austin, Austin, Texas; the Department of Languages and Linguistics, University of Texas at El Paso, El Paso, Texas; the College of Nursing, New York University, New York, New York; and Ibis Reproductive Health, Oakland, California.
See related articles on pages 558 and 566.
Funded by a grant from the Eunice Kennedy Shriver National Institute of Child Health and Human Development (R01HD047816).
The authors thank Sandra G. García, Leticia Fernández, and the late Charlotte Ellertson for contributing to the design of the project and helping to write the original proposal; Victor Talavera for project management; and Kari White for analysis and database management.
Presented at Reproductive Health 2010, September 23, 2010, Atlanta, Georgia. Preliminary versions were presented at the Annual Meeting of the Population Association of America, April 30–May 2, 2009, Detroit, Michigan, and at the XXVI IUSSP International Population Conference, October 1, 2009, Marrakech, Morocco.
Corresponding author: Joseph E. Potter, PhD, Population Research Center, University of Texas at Austin, 1 University Station G1800, Austin, TX 78712; e-mail: email@example.com.
Financial Disclosure The authors did not report any potential conflicts of interest.