Boys and Puberty

Last Updated August 2022 | This article was created by editorial staff and reviewed by Kyle Bradford Jones

Puberty is defined as the period or age at which a person is first capable of sexual reproduction of children.

For boys, puberty represents a time of change, both physically and emotionally. While boys will often hear things about puberty through school, media influences, and friends, it’s important for your son to learn about the changes from you and his doctor.

The timing of puberty is different for each boy. However, it usually starts between the ages of 9 and 16. Boys generally start puberty two years later than girls. This can be frustrating for boys as they watch girls maturing and growing taller.

Path to improved well being

Change can be scary, confusing, and exciting for a boy experiencing puberty. Your son may want to know how tall he will get, why his voice is changing, or when he can shave for the first time. Break it down for him by explaining the stages of puberty. These stages will affect him physically and emotionally.

Share with him the following changes that will occur during puberty:

Changes to his body

Your son will notice a growth spurt in his hands and feet. His hands and feet will probably appear out of proportion from the rest of his body. It may contribute to clumsiness. Eventually, your son will notice a significant increase in his height. If he was overweight as a child, he might appear to have lost weight as he inches up. By the time a boy has reached the end of puberty, he may have grown 14 inches taller and 40 pounds heavier. Also, your son’s neck may thicken, his shoulders will broaden, and his hips will widen. His facial bones will change, and his jaw line will become more defined. He’ll start to look like a man. Your son will start to sound like a man, too. His voice will crack for months as his voice goes from that childlike quality to the deep tone he’ll have as an adult.

Body hair will slowly appear on your son’s body and get thicker as he nears the end of puberty. Small amounts of hair will begin under his arms, the hair on his legs and arms will become more noticeable. He will begin to get pubic hair around his penis and scrotum. Chest and facial hair begin to appear. It becomes more prominent near the end of puberty. Your son may have to shave once a week the first few years of high school. He also may see an increase in pimples, sweating under his armpits and body odor. Daily hygiene will be important.

Your son’s genitals will change, too. His penis and testicles will get larger. He’ll have more frequent erections, which is when his penis becomes hard, larger, and straightens out from his body. Sometimes, an erection leads to ejaculation, which is when semen comes out of his penis. Ejaculations can happen at any time, including at night. Some call this a “wet dream.” This happens when a boy’s testosterone level rises. Semen does have sperm in it. Once your son begins puberty, his semen can fertilize a woman’s egg and make a baby during sexual intercourse.

Half of all boys may experience a condition that causes their breasts to become enlarged. However, the condition usually disappears after 6 months to 2 years.

Finally, many boys will find that their muscles develop as they go through puberty. Even if they don’t lift weights, boys may see their muscles become more defined.

These changes occur because of new hormones that lead to growth and change in the body. Not all boys will experience the same changes at the same time. Each boy moving through puberty may have different timelines and experiences.

Changes to emotions and thinking

Boys will experience a range of emotions as they go through puberty. At times, they may feel irritable, sad, and even depressed. They may feel many different emotions related to their sexuality, including desire, confusion, and fear. Emotions start to level out by the end of puberty. Your son will likely show more independence from mom and dad and have more interest in developing closer bonds with friends and love interests. Their work and organizational habits may improve, as will their plans for their future.

Things to consider

Most boys sail through puberty with little more than embarrassment over their changing voice, acne, unexpected erections, fluctuating hormones, and emotions. However, see your doctor if your son:

  • Hasn’t started puberty by age 14.
  • Has pains associated with his growth spurt.
  • Has acne that seems worse than normal.
  • Experiences moods or depression that are more troubling than what you expected.
  • Has thoughts of suicide or of harming himself or others.

Questions to ask your doctor

  • My son stopped growing at an early age. Should I be concerned?
  • At what age could my son father a child?
  • What medicine can my son take for his acne?
  • What are the signs of a moody teenager versus something more serious?
  • My son seems dominated by his interest in all things related to sex (or seems to have no interest at all). What is normal?