Introduction

The health of adolescents has a significant impact on global health. Today, there are more than 1.5 billion adolescents and young adults aged 10 to 25 worldwide (UNFPA, 2003). Representing a large proportion of the global population, the health of these young people will greatly affect the overall health of the world as they become adults and begin families of their own. Adolescence, the transition from childhood to the roles and responsibilities of adulthood, critically sets the life-course (McIntyre et al., 2002). Among the many challenges to the health and well-being of adolescents during this second decade of life – poverty, violence, and communicable diseases, to name a few – sexual and reproductive health issues are paramount. And unsafe sex continues to be a key risk factor for death and illness among adolescents, worldwide. Indeed, in developing countries risky sexual behavior is ranked higher than unsafe water and poor sanitation, and is second only to being underweight (Glasier et al., 2006).

Primary negative outcomes associated with unsafe sex during adolescence are early pregnancy and sexually transmitted infections (STIs), including HIV/AIDS, all of which have the potential to affect the entire life-course of adolescents. At the same time, prevention of these negative outcomes during adolescence has the potential to change the lives of many adolescents, and in turn, adults (Bearinger et al., 2007).