Adolescence is a time of significant physical, emotional, and social changes. As parents, understanding your son’s sexual and reproductive health is key to providing guidance and fostering open communication. Although most of these changes start during the middle school years (ages 11-14), it’s not unusual for them to begin as early as age 9 and as late as age 15. Genetics plays a big role in when puberty begins and when it ends. Most changes are completed by late adolescence or young adulthood. It is important to note that all males go through the same stages of pubertal development but at different rates and timing. Testosterone mediates most of the changes in males. These materials should help you navigate the many health issues you may experience as the parent of a young male.