Early sexual debut is associated with drug use and decreased educational attainment among males and females in Kisumu County, Kenya.

Differing global sociocultural contexts of sexual relationships influence age at first sexual intercourse with potentially long-lasting region-specific effects such as increased risk of contracting HIV and other sexually transmitted infections (STIs). In these cross-sectional analyses of data from the screening and enrollment visits for an HIV incidence study in Kisumu County, Kenya, we evaluated factors associated with having experienced an early sexual debut (ESD) among males and females aged 18-35 years. Clinical evaluation was performed and sexual behaviors were assessed via questionnaire. ESD was defined as self-reported age 15 years or younger at first sexual intercourse. Robust Poisson regression was used to estimate prevalence ratios (PRs) and 95% confidence intervals (95% CIs) for factors associated with ESD. Of 1057 participants, 542 (51.3%) were female. Participants' median age at study screening was 25 years (interquartile range [IQR]: 22-29), and at sexual debut was 16 years (IQR: 14-17). Five hundred and four participants (47.7%) reported ESD. ESD was less common among females (PR 0.78, CI 0.67-0.90) and participants with more than primary education (PR 0.56, CI 0.47-0.66). ESD was more common in participants with a history of drug use (PR 1.28, CI 1.10-1.49). Drug use removed the protective effect of education (some secondary education or less, no drug use: PR 0.72, CI 0.61-0.85; some secondary education or less, drug use: PR 0.94, CI 0.74-1.18). ESD was common in our study and associated with lower educational attainment and increased likelihood of drug use. Interventions are needed early in life, well before 15 years of age, to encourage engagement in schooling and prevent drug use. Comprehensive sexual education and interventions to prevent drug use may be beneficial before the age of 15 years.