May 2014

Numbers matter; they affect our lives. This is especially so when it comes to contraceptive efficacy. Unfortunately, the numbers clinicians give women can be hard to relate to. For example, telling a woman that Nexplanon has a 0.05% first-year failure rate is not as easy for her to imagine as telling her that in one year 5 women among 10,000 using the method will get pregnant. Using these simplified numbers—without decimals and symbols—is not only easier to understand, but it is easier for making comparisons. The average women can more directly understand the difference when told that the number of women who get pregnant out of 10,000 users is 5 using Nexplanon and 900 using pills. We have developed a table that more clearly lays out the contraceptive failure risks. Please feel free to copy and use the table with your own patients.

– Robert A. Hatcher, MD, MPH, professor emeritus of obstetrics and gynecology, Emory University School of Medicine