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Updated: Aug 29, 2026

Precision Implementation of Minimal Erythema Dose (MED) Testing to Assess Individual Variation in Human Inflammatory Response
Published on: October 3, 2019
Abstract:
Evra (Janssen-Cilag) is the first contraceptive to be available as a skin patch. In promotional material aimed at healthcare professionals, the company claims that Evra offers a "once-weekly method of contraception" with "more than 99% effectiveness and excellent compliance". The company's website for women using Evra carries the slogan "Evra The Right Contraceptive Choice" and claims that the patch is "just as effective as the contraceptive pill". Each patch is intended to be worn for 7 days, in contrast to combined oral contraceptives (COCs), which need to be taken daily. Here we assess whether Evra offers real advantages over COCs and consider its place as a contraceptive option.
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