Efficacy
November 17th, 2005Failure rates have been documented to range from 1. to 9. per 100 women in the first year of use. The failureure rate is higher in youthfuler women (3. per 100 woman-years) compared to women over age 40 (0. per 100 woman-years). In motivated women, the failureure rate is comparable to the actual use rate with combination oral contraception.