A new study of the sexual habits of nearly 85,000 young people suggests that males are at least ten times more likely to engage in high-risk sexual behaviour than their female counterparts.

Writing in the SAHARA-J: Journal of Social Aspects of AIDS/HIV, Yifru Berhan and Asres Berhan sift through data from from the Demographic and Health Surveys data (21 from sub-Saharan Africa plus Bolivia, Cambodia, Guyana, Haiti and Vietnam) in order to understand how the practices of young males and females differed. They also investigated the influence that age, wealth and educational background had on their sexual behaviour.

Some of their findings are unexpected. Berhan and Berhan found that males aged 15-19 were 27 times more likely than females the same age to indulge in high-risk behaviour, which for the purposes of this study was defined as having unprotected heterosexual sex with non-regular partners during the last year.

The data also suggested that living in an urban area, being well educated, belonging to a higher economic group and, importantly, just being a young male, made a person more likely to take chances - a dangerous habit that can last well into adulthood.

The authors conclude: "In the majority of the included countries, the susceptibility of male youths to higher risk sex was significantly higher than the female youths regardless of the assessed independent variables (sex, age, education, residence and wealth index) ... The consistent and strong association of higher risk sex with male youth is probably strong evidence to surmise that being a male youth is a strong predictor of practicing higher risk sex than the other assessed variables."

The fact that urban and well-educated youths - who might be considered to be more aware of and able to avoid risks - were more inclined to take them puzzled the pair. In the absence of other research, Berhan and Berhan suggest that the generally younger age of marriage for females as well as the fact that males have higher rates of substance abuse, are more likely to have multiple partners and first have sex at younger age may all play a part.

These findings are timely. According to the WHO and UNAIDS, around 50% of new HIV infections occur in young people, with higher-risk sex a key factor.

Berhan and Berhan's findings should help educators, health workers and families better understand patterns of male sexual risk-taking and tailor their interventions accordingly to bring about long-lasting - and potentially life-saving - behavioural change.