Original researchExtending the time limit for starting the Yuzpe regimen of emergency contraception to 120 hours☆
Section snippets
Materials and methods
In parallel to a double-masked randomized controlled trial of two modifications to the Yuzpe regimen of emergency contraception,8 we conducted a prospective, observational study to evaluate the effectiveness of the Yuzpe regimen when started between 72 and 120 hours after unprotected intercourse (ie, on days 4 or 5) among women refusing copper IUD insertion. We compared failure rates observed in this cohort to rates among otherwise similar women assigned to the control group of the companion
Results
Women enrolled in the observational days 4–5 cohort were similar to those in the standard Yuzpe control arm from the randomized study (Table 1). In both groups, the mean adjusted cycle day of unprotected sex was approximately the same (adjusted cycle day 13). Women in both groups were in their early 20s (mean age 22 years in the days 4–5 group and 24 years in the standard Yuzpe control group). Body mass index was similar (mean 24 in the days 4–5 group and 23 in the standard Yuzpe group). Three
Discussion
Our study suggests that the 72-hour cutoff after unprotected intercourse for starting the Yuzpe regimen of emergency contraception is unnecessarily restrictive. This result is consistent with the finding from a recent, similar Canadian study,9 as well as with a study of levonorgestrel recently published by the World Health Organization.6 Women who present seeking emergency contraception later than the 72-hour cutoff should be counseled that insertion of a copper IUD is the most effective way to
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Cited by (0)
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The authors represent a larger study team that includes Katrina Abuabara, Alison Bigrigg, Kelly Blanchard, Sarah Carlson, Joanne Gallagher, Anna Glasier, Sue Haskell, Bridget Hinchcliffe, Chris Hesketh, Janice Hunt, Helen King, Becca Loftus-Granberg, Chris McCaig, Tara Shochet, Abigail Norris Turner, Annik Sorhaindo, Alex Stirling, Anne Tyrer, Kate Weaver, and Anne Webb.
The trial was supported by grants from the William and Flora Hewlett Foundation, David & Lucile Packard Foundation, Open Society Institute, Mary Wohlford, John Snyder, the Population Council, an anonymous donor, and Irving and Roberta Schneiderman. Funders did not participate in implementing any stage of the study.