Oral contraceptive continuation along the USA-Mexico border: does a prescription or the number of pill packs dispensed matter?

Joseph E. Potter, University of Texas at Austin
Sarah McKinnon, University of Texas at Austin
Daniel Grossman, Ibis Reproductive Health
Kristine Hopkins, University of Texas at Austin
Daniel A. Powers, University of Texas at Austin
Michele Shedlin, University of Texas at El Paso
Jon Amastae, University of Texas at El Paso

In this paper, we present life table results that compare continuation rates over a nine month period for pill users who last obtained their method at a family planning clinic in El Paso, Texas, USA with users who last obtained their pills over-the-counter at a pharmacy across the border in Ciudad Juarez, Mexico. We then carry out a hazards analysis of both all cause discontinuation, and discontinuation rates that exclude the risk of discontinuing in order to get pregnant or switch a method. These models include time-varying covariates for the number of pill packs at last supply and where they were obtained, as well as parity and duration of use at baseline. The results provide support for removing the medical requirements for obtaining oral contraception in the US, as well as the recent finding that continuation can be improved by providing a larger number of cycles at clinic visits.