Contributions of side effects to contraceptive discontinuation and method switch among Kenyan women: a prospective cohort study.

OBJECTIVE To determine the contribution of specific contraceptive side effects to method switch and modern-method discontinuation among Kenyan women. DESIGN A prospective cohort study. SETTING Five counties in Western Kenya. PARTICIPANTS Women aged ≥18 years old and emancipated female minors ≥14 years old using modern, reversible contraception were recruited while attending 10 public health facilities. METHODS Patient-reported side effect symptoms, method switch, and discontinuation were reported through weekly text message-based surveys for 24 weeks. MAIN OUTCOME MEASUREMENTS Prevalence, hazards ratio (HR). RESULTS Among 825 women, 44% were using implants, 43% injectables, 7% intrauterine device, and 6% oral contraceptive pills at enrollment. Most (61%) women were continuing a method used in the previous month. During the 24-week follow-up, incidence of contraceptive switch was 61.3 per 100 person-years (95% confidence interval [CI] 52.4-71.8) and incidence of discontinuation was 38.5 per 100 person-years (95%CI 31.6-47.0). On average, one-quarter (prevalence [Pr] 0.24, 95%CI 0.22-0.26) of participants reported side effects or method problems weekly, with sexual side effects the most prevalent symptom (Pr 0.15, 95%CI 0.13-0.16). Lack of expected bleeding was associated with higher risk of method switch (adjusted hazard ratio [aHR] 2.36, 95%CI 1.22-4.57). Risk of all-modern method discontinuation was higher among women experiencing irregular bleeding (adjusted hazard ratio [aHR] 2.39, 95%CI 1.20-4.77), weight changes (aHR 2.72, 95%CI 1.47-4.68), and sexual side effects (aHR 2.42, 95%CI 1.40-4.20). CONCLUSIONS Addressing irregular bleeding, weight changes, and sexual side effects through development of new products that minimize these specific side effects and anticipatory counseling may reduce method-related discontinuation.