Riboflavin, self-report, and serum norethindrone. Comparison of their use as indicators of adolescent compliance with oral contraceptives.

The purpose of this study was to test the reliability of using the tablet marker, riboflavin, as an indicator of adolescent compliance with oral contraceptives, as compared with self-reports and more costly quantitative determinations of serum norethindrone levels. In a pilot study, a total of 31 urine samples were obtained from 11 subjects, aged 14 to 18 years. A follow-up study was conducted on 26 girls, aged 14 to 19 years, who were randomly selected from an ongoing study of oral contraceptive compliance. Subjects were given an oral contraceptive (Ortho-Novum 1/35), combined with 28 mg of riboflavin. In both studies, urinary fluorescence tests for riboflavin and self-reports were found to be significantly associated. In the follow-up study, both self-reports and urinary fluorescence tests were significantly associated with serum norethindrone levels. When the urinary fluorescence test agreed with self-report, compliance or noncompliance was confirmed by serum norethindrone levels in 90% of the cases. The findings suggest that riboflavin, combined with self-report, can be used as an accurate and cost-effective indicator of adolescent compliance with oral contraceptives.