Contraception with the cervical cap: effectiveness, safety, continuity of use, and user satisfaction.
With the growing interest in barrier contraceptive methods, the cervical cap has come back into use in North America. We examined the cap's effectiveness, safety, continuity of use, and user satisfaction among 617 women who were fitted at a family planning clinic in Toronto, Canada, between May 1981 and November 1983. Follow-up information was available for 516 of these women. Using a life table analysis with Bayesian adjustment, the probability of becoming pregnant after 12 months of use was 0.166 with a standard error of 0.022. There is evidence that after 1 year of use the caps deteriorate and that this deterioration may increase the risk of pregnancy. Many of the women in this study were very satisfied with the cervical cap; however, such problems as dislodgement, discomfort to user and partner, difficulty with insertion and removal, and unpleasant odour affected acceptability and continuity of use. It is likely that these problems could be alleviated by improving the quality of or changing the materials, modifying the design to improve the fit, and providing a greater range of sizes.