Thesis (Master's)--University of Washington, 2017-06Objective: The objective of this study is to prospectively measure contraceptive use throughout the postpartum period among Kenyan women and characterize trends in postpartum contraceptive initiation, discontinuation, and method switch. Design: Prospective cohort study Methods: We conducted an analysis of postpartum contraceptive use among a cohort of women enrolled in a study aimed to measure maternal HIV acquisition during and after pregnancy in western Kenya. Women were enrolled in the parent study during antenatal care (ANC) and were eligible for this analysis if they remained HIV-seronegative throughout pregnancy and through 9 months postpartum and had at least one postpartum study visit. At study visits (scheduled at 2, 6, 10, 14 weeks; 6 and 9 months postpartum), women completed questionnaires to assess maternal health, sexual behavior, and contraceptive use (postpartum only). Contraceptive use was categorized as modern contraception (all methods of contraception excluding natural methods), highly effective contraception (all modern contraceptive methods excluding barrier methods), and long acting reversible contraception (LARC; intrauterine devices (IUD) and implants). Generalized linear models and Cox proportional hazards regression models were used to identify cofactors associated with contraceptive use during the postpartum period and time to contraceptive initiation and discontinuation, respectively. Results: Overall, 1257 postpartum women were included in the analysis. Median age was 22 years, 78% were married, median relationship duration was 4 years, and 68% of women were multiparous. Overall, 739 women (59%) used modern contraception, 623 (50%) used highly effective contraception, and 116 (9%) used LARC during the postpartum period. Injectable contraceptives, condoms, and OCPs were the most common methods used (45%, 22%, and 21% of contraceptive users, respectively). Among 739 women who initiated contraception, 8% discontinued use and 16% switched to a different method in the postpartum period. During 6095 person-months of follow-up, the incidence of initiation of modern contraception was 11.7/100 person-months (95% confidence interval [CI]: 10.9-12.6). Women who had resumed sexual activity, higher education, and a history of interpersonal violence were more likely to use contraception; women who had experienced pregnancy loss were less likely to use modern contraception postpartum compared to women with live births in the most recent pregnancy (HR, 95% CI). The modern contraceptive discontinuation rate was 0.63 per 100 person-months (95% CI 0.49-0.81) and discontinuation was associated with being employed and cessation of breastfeeding. Conclusion: While uptake of modern contraceptives was high among postpartum Kenyan women, discontinuation rates and method switching were common. Further research is needed to understand reasons for method discontinuation, to guide improved counseling messages
