Birth Control Pills May Fail In Women With Certain Genetic Variant

BOSTON (CBS) – While birth control pills are one of the most effective ways to prevent pregnancy, they don't work 100 percent of the time. The small failure rate was largely thought to be due to human error, like a woman missing a dose.

But a new study from the University of Colorado finds that some women may be more likely to get pregnant on the pill due to their genetics, not their forgetfulness.

Researchers looked at 350 women with hormonal implants, like Nexplanon, which are small plastic strips placed in a woman's upper arm that slowly release hormones to prevent pregnancy.

They found that women with a certain genetic variant break down hormones so quickly, it could put them at risk for pregnancy, especially if they're on low dose formulations.

Researchers say it's important to know that women metabolize hormones differently and future studies will hopefully help doctors figure out how to give the right medication to the right patient.