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Updated: Jul 1, 2025

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Published on: August 13, 2019
Evaluation of adherence to a daily progestin-only pill in a simulated over-the-counter setting
Irene Laurora1, Brandon Henrie2, Hélène Guillard1
1HRA Pharma, A Perrigo Company, Global Women's Health, Chatillion, France.
Objective:
The Adherence with Continuous Dose Oral Contraceptive: Evaluation of Self-Selection and Use (ACCESS) study assessed whether consumers can adhere to the regimen for a progestin-only pill (norgestrel 0.075 mg) in an over-the-counter (OTC) setting.
Study Design:
An actual use study in a simulated OTC environment assessed adherence to directions to take norgestrel 0.075 mg every day at the same time in 883 participants for up to 24 weeks.
Results:
Eighty-five percent (747/883) of participants reported ≥85% adherence to taking norgestrel 0.075 mg every day and reported taking their dose within three hours of their scheduled dosing time on 96% of days. When accounting for use of a condom for 48 hours if a pill was missed, participants reported correctly following the label's directed use for 97% of doses overall, with 95% of participants following label directions for ≥85% of doses. The main limitations were related to finding a balance between intensely collecting data to ensure accurate assessment of adherence and leaving users to behave as they would in a real OTC situation without healthcare practitioner intervention. We observed that some participants reported taking more doses than they could have based on the supply of medication given to them. To fully examine the situation, and the impact on the conclusions, additional post hoc sensitivity analyses were performed, and showed remarkably consistent results.
Conclusions:
Consumers were highly adherent to taking norgestrel 0.075 mg when using only the information provided by the proposed OTC label.
Implications:
Adherence to a daily oral contraceptive pill was high when obtained OTC. This suggests that effectiveness of an OTC pill is likely to be like that of a prescribed pill and easier access to this effective contraceptive should allow more opportunity to prevent pregnancy.
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