Purpose: Imperfect oral contraceptive pill (OCP) regimen adherence may impair contraceptive effectiveness. The purpose of this study was to describe daily adherence patterns of OCP use, to analyze OCP protection on an event level basis, and to examine pill-taking and condom use during method transitions. Methods: Women (n = 123, ages 14-17 years) completed quarterly interviews to classify OCP method choice into four categories: stable, initiated, stopped, and discordant use. Within each OCP category, daily diaries were used to assess occurrence of coitus, condom use, and patterns of day-to-day OCP use (i.e., consecutive days of OCP use reported with no more than two consecutive days of nonuse). A coital event was OCP protected if pills were used on both the day of the coitus and the day preceding. Results: There were 123 participants who reported at least some OCP use in 210 diary periods (average diary length = 75.5 days). Fifty-three participants categorized as stable users reported 87 diary periods: the average interval of consecutive OCP use in this group was 32.5 days. Among stable users, only 45% of coital events were associated with both OCP and condom use. Over one-fifth of coital events in all groups were protected by no method of contraception. Conclusion: Dual use of OCP and barrier contraception remains an elusive goal. The time during OCP adoption or discontinuation is often unprotected by condoms. However, concurrent missed pills and condom nonuse increase pregnancy and infection risk even among stable OCP users. Understanding motivation for method usage may improve education and prevention techniques.
- Coital event
ASJC Scopus subject areas
- Pediatrics, Perinatology, and Child Health