The effect of pack supply on oral contraceptive pill continuation: a randomized controlled trial.

Abstract

The often small number of oral contraceptive pill (OCP) cycles provided may contribute to high rates of discontinuation. We examined the effect of an increased OCP supply on 6-month continuation rates. This was a randomized trial of women initiating OCP use at an urban family-planning clinic (n=700). All participants were randomized to receive three or seven cycles of OCPs. Participants younger than age 18 years or uninsured received their entire supply as packs; those older than age 18 years with insurance were additionally randomized to receive either packs or a prescription for refills. We contacted participants by telephone 6 months after enrollment to assess OCP continuation and adverse events. We obtained follow-up information from 76% of participants (260 of 342 in the three-pack group, 244 of 319 in the seven-pack group). Participants who received seven packs had higher 6-month continuation than participants who received three packs (51% compared with 35%, P<.001). The treatment effect was greater among participants younger than 18 years of age (49% compared with 12%, P<.001) than among those aged 18 years and older (52% compared with 40%, P=.018). Participants who received a prescription were less likely to continue OCP use than those who received packs (42% compared with 21%, P=.027). Adverse events in the study were rare and not associated with receiving more OCP packs. A greater OCP supply at the time of initiation can improve continuation rates, especially among women younger than 18 years of age. ClinicalTrials.gov, www.clinicaltrials.gov, NCT00677742. I.