ABSTRACT
OBJECTIVES: To develop a model to estimate the possible impact of use of an over-the-counter (OTC) progestin-only pill (POP) on the number of unintended pregnancies in the United States. STUDY DESIGN: Using typical use failure rates (7% for POPs), we compared the expected number of unintended pregnancies for two theoretical cohorts of 100,000 women: one which purchased and used an OTC POP exclusively for contraception, the other using contraceptive methods at proportions obtained from an actual-use clinical trial simulating OTC use of norgestrel 0.075 mg (including 35% using no method and only 19% using hormonal contraception or long-acting contraceptives). Sensitivity analyses were conducted using alternative model inputs such as different failure rates for OTC POPs and varied alternative contraceptive method mix. RESULTS: An estimated 37,624 unintended pregnancies would occur annually if 100,000 women continued their usual contraceptive method as used at baseline in the actual use trial. This would be reduced by 81% to 7,000 pregnancies with the exclusive use of an OTC POP - a net reduction of 30,624 unintended pregnancies annually. While the number of unintended pregnancies prevented varied as the model parameters were modified (ranging from 1,461 to 34,124), a net benefit of OTC POP use was observed over a wide range of input values. CONCLUSIONS: Using data from a real-world contraception user profile, our model suggests that use of an OTC POP could reduce the overall number of unintended pregnancies in the United States. This conclusion remains true across a wide range of modeled scenarios. IMPLICATIONS: The estimates suggested by this model are supportive of an OTC switch for a POP.
