How can I prepare my son for puberty?

Editor's note: We will feature a blog post on preparing daughters for puberty next month.

You know your child is going to hit puberty, so the smart parent talks with the child about his body from the time he's in diapers. But if you've waited until your boy's body has started sprouting hair in places where only grownups have it, then it's time to get on the stick.

Puberty is when hormonal changes trigger the development of secondary sex characteristics, such as wide hips or breasts in females, and facial hair and stronger muscle tone in males. The sexual and reproductive organs also change. The changes heighten the ability to experience sexual stimulation, and enable the body to reproduce. For a child, this can be a delightful time of pride in their own maturing body, or a terrifying time of incomprehensible changes. In the United States, puberty can start as early as 8; the American Academy of Pediatrics  suggests that a boy see a physician if there are no signs of puberty by age 14, and a girl by age 13.

A few key pieces of information can make all the difference to a child's comfort as his body changes. Today's article focuses on boys; advice for parents of girls will follow next month. Both genders, however, need information about the other, and you should share them as matters of medical fact.

People tend to focus on the genital changes when they think of puberty, and so we'll start there. Boys going through puberty may be extremely sensitive to thoughts, feelings or images that lead to sexual arousal. Penile erection is the first sign of sexual arousal in males, and boys entering puberty may become embarrassed by unanticipated erections.

The most important fact a parent can share with a boy is that sexual arousal is an automatic reflexive response, controlled by the part of their brain that controls things like breathing. We don't decide to breathe; our brain makes sure we do! Parents can provide a soft landing into this confusing world of bodily changes by helping a boy to understand that unexpected erections are a normal, natural part of growing up, and not something he can control or should be ashamed of.

Most kids with access to the internet will see and be aroused by on-line pornography presenting a special challenge for parents. Check out this advice from Prevent Child Abuse America on this growing problem.

For most boys in puberty, sexual arousal will periodically culminate in orgasms either while sleeping or stimulating themselves. Male climaxes generally include the discharge of semen. Parents can ease their son through the mystery of these nocturnal emissions by explaining that this is a normal, healthy part of growing up. Share that that ejaculate is typically about 20 percent sperm surrounded by other fluids the body produces to help keep the sperm alive and moving.  Remind boys that this sperm can create a baby, and strongly consider showing him a condom, or at least an article written for boys on how to use them. Family rules should also allow for privacy, especially if a child shares his bedroom with a sibling.

Ideally, curiosity or pride will accompany early sexual feelings; a little confusion may even be OK. But it's critical to keep negative feelings, such as fear, guilt or shame, out of the mix; we don't want your child to associate negative emotions with sexual arousal. At best, it can inhibit enjoyment of a healthy sex life; at worst it could develop into pathology where sexual arousal can only be achieved when the negative emotions are present.

Finally, talk to your boy about consent. Some boys think that because arousal happens with a partner, the partner caused it and therefore is responsible for relieving it. Helping your son learn that the arousal was caused by his own brain and hormones will make him a safer date. If he does encounter a person who stimulates him purposely to leave him frustrated, he should eliminate that person from his social life immediately.

Watching a child grow and mature is a joy for parents, but it's our job to keep them safe and healthy along the way.

Rosenzweig is also author of The Sex-Wise Parent  and   The Parent's Guide to Talking About Sex: A Complete Guide to Raising (Sexually) Safe, Smart, and Healthy Children.    For more information, read her blog , follow @JanetRosenzweig on Twitter.

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