Background: The study aimed to examine the impact of household composition and satisfaction with family life on sexual behaviours among high school male and female students (aged 11-22 years) in Hong Kong.; Method: High schools were randomly selected, and the final sample comprised 25 schools. Students were divided into two groups ('living with both biological parents' vs 'not living with both biological parents'). Students were asked to rate their satisfaction with family life on a five-point Likert scale in a self-administered questionnaire. Dependent variables were sexual experience, sexual harassment, sexting and nude chats. Multiple logistic regression was used to analyse the results.; Results: 3907 students were included in the analysis. 202 students (5.2%) were sexually active. 505 students had ever (13.0%) sexually harassed others and 303 students (7.8%) had ever been sexually harassed by others. 58 students (1.5%) had ever had nude chats. 1005 students (25.8%) had sexted in the last 12 months. Students who lived with both biological parents were less like to be sexually active, to sext and to have nude chats than those who did not. Students who had higher family life satisfaction were less likely to be sexually active, to sexually harass others, to be sexually harassed by others, to sext and to have nude chats than students who had lower satisfaction with their family life.; Conclusions: Sexual health programmes and interventions should consider family functioning. Students who have low family satisfaction and those who do not live with both their biological parents should be targeted for sexual health interventions.
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Background: Little is known about sex knowledge, attitudes, and high-risk sexual behaviors among unmarried youth in Hong Kong. It is of public health importance to investigate this topic to inform sex education, policymaking, and prevention and intervention programs. Methods: Based on the Youth Sexuality Survey conducted by Hong Kong Family Planning Association (FPAHK) in 2011, this study explored the characteristics of sexual knowledge, attitudes, and high-risk sexual behaviors among 1,126 unmarried youth aged 18 to 27 years. Multiple logistic regressions were performed to examine factors associated with unmarried youth's premarital sex, casual relationships, multiple sex partners, and premarital pregnancy. Results: Unmarried youth in Hong Kong had adequate sex knowledge, but contraceptive knowledge was deficient. The majority of unmarried youth (63.8%) held liberal attitudes toward premarital sex and about half held liberal attitudes toward any form of sexual activity and premarital pregnancy. Around 60% held conservative attitudes toward causal sex relationships and multiple sex partners. Males tended to hold more liberal attitudes toward high-risk sex behaviors than female youth. Approximately 41.5% of unmarried youth reported having engaged in premarital sex, whereas less than 10% engaged in high-risk sexual behaviors. Males also reported higher amounts of premarital sex, casual sex relationships, and multiple sex partners. Females reported higher levels of sexual coercion. Logistic regressions indicated that being older, coming from a divorced family, out of school status and liberal attitudes toward risky sex behavior were more likely to engage in premarital sex or high-risk sex behaviors, and being female, being better educated and being immigrants were less likely to engage in premarital sex. However, being immigrants was more likely to engage in casual relationship and to have multiple partners. Conclusions: Premarital sex is becoming more prevalent among unmarried