Sexual risk behaviour and its correlates among adolescents in Indonesia, Laos, Thailand and Timor-Leste: results from national school surveys in 2015.

Objectives The study aimed to assess the prevalence and correlates of sexual risk behaviours among adolescents in four Southeast Asian countries. Methods In the cross-sectional "Global School-Based Student Health Survey (GSHS)", 24,423 adolescents (mean age 14.1 years, SD=1.7) from Indonesia, Laos, Thailand and Timor-Leste responded to a questionnaire in 2015. Results Overall, 8.5% of the students (11.0% males and 6.3% females) ever had sex, ranging from 5.3% in Indonesia to 26.4% in Timor-Leste. Among the sexually active, 49.3% (55.9% males and 36.8% females) had their first sexual intercourse before the age 14 years, ranging from 16.1% in Laos to 73.9% in Indonesia, 59.7% (62.6% males and 53.5% females) had multiple sexual partners, ranging from 55.5% in Timor-Leste to 63.4% in Indonesia, 46.9% (46.8% males and 46.5% females) did not use a condom at last sex, ranging from 37.0% in Thailand to 65.3% in Indonesia, 49.8% (53.7% males and 43.7% females) had not used or did not know of the use of birth control at last sex, ranging from 40.6% in Thailand to 61.5% in Timor-Leste, and 54.2% (54.9% males and 47.0% females) engaged in multiple sexual risk behaviour, ranging from 45.9% in Laos to 78.0% in Indonesia. In adjusted logistic regression analysis, male sex, older age, food insecurity, tobacco use, alcohol use, ever cannabis and/or amphetamine use, psychological distress, and school truancy were associated with two or more and/or multiple sexual risk behaviours. Conclusions A high proportion of students engaged in various sexual risk behaviours calling for a scale up comprehensive sexuality education and integration of substance use and mental health into such intervention programmes in this adolescent school population.