Most boys also start puberty now. Their testicles and penis begin to grow, as does their underarm and pubic hair. A growth spurt ensues. Their voice becomes deeper and facial hair starts to grow. Boys have their first ejaculation at the age of 13 (on average), which is a sign that they are sexually mature and can father a child.
Girls also continue to develop. They have already had a growth spurt and now develop underarm and pubic hair. Girls have their first menstrual period at the age of 10 (on average), indicating that they are sexually mature and could become pregnant.
Masturbation may increase, more among boys than among girls.
Adolescents can be very unsure about the growth of their bodies: “is it normal?”, “are they developing too slowly compared with others the same age?”
Adolescents have to get used to their “new body”, often feeling embarrassed and uncomfortable.
Young people develop a sexual self-image: they see themselves as someone who can have sex, which is why it is important for them to be attractive. Since they are often unsure about their own body, they are often equally unsure about how attractive they are (to a potential partner).
Young people of this age are frequently very sensitive to the opinion of others: they can be influenced by their peers.
They also start finding people of the same age sexually attractive.
Boys and girls gradually find out whether they fancy boys or girls (sexual orientation).
They often truly fall in love for the first time. They flirt with one another and have their first relationships.
More experience with kissing and caressing; petting.