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A Clinical Trial Assessing the Safety, Efficacy, and Delivery of Olive-Oil-Based Three-Chamber Bags for Parenteral Nutrition
Published on: September 20, 2019
The effect of pack supply on oral contraceptive pill continuation: a randomized controlled trial
Katharine O'Connell White1, Carolyn Westhoff
1From the Tufts University School of Medicine/Baystate Medical Center, Springfield, Massachusetts; and Columbia University and New York Presbyterian Hospital, New York, New York.
Objective:
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.
Methods:
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.
Results:
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.
Conclusion:
A greater OCP supply at the time of initiation can improve continuation rates, especially among women younger than 18 years of age.
Clinical Trial Registration:
ClinicalTrials.gov, www.clinicaltrials.gov, NCT00677742.
Level Of Evidence:
I.
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