Puberty often begins between the ages of 9 and 14 in young men. Puberty that occurs before age 9 can prematurely stop growth and can be emotionally difficult for boys and their parents. In some cases, puberty can start when the boy is just a toddler. This is called precocious puberty (puberty before age 9) and is directly linked to premature release of gonadotropins from the pituitary.
There are two types of precocious puberty. The first (and most common) is called central precocious puberty. This is caused by gonadotropins being released from the pituitary too early, causing testosterone production from the testicles. The second type is more rare and is called peripheral precocious puberty. This is not a signal from the boy’s pituitary gland but can be caused by tumors in the adrenal glands or testicles. It can also be caused by exposure to testosterone replacement products such as coming into contact with their father’s testosterone replacement gel (simply touching the skin the gel was applied to or clothing that has covered the gel).
Regardless of the cause, precocious puberty can lead to emotional issues as the child goes through “manhood” at a very, very young age. It can also cause growth stunting. Although the boy will have a quick and rapid growth spurt with precocious puberty, the growth plates will fuse early leading to them actually being shorter than their peers in the long run. For these reasons, treatment is often recommended. If you notice signs of puberty in your boy prior to age 9, consult with a pediatrician. Medications that suppress gonadotropins, such as leuprolide, can be administered to stop the puberty from progressing. These medications are then removed at about age 9 to allow the boy to begin puberty. For boys exhibiting signs of puberty who have a family member who uses topical testosterone, seeing a healthcare provider is still important. Men in the home who use testosterone may want to consider switching to an injectable form of testosterone to prevent exposing their young child to testosterone either through skin touching or exposure to clothing. Testosterone can even be transferred when laundering dad’s clothes with his child’s. Washing dad’s clothes separate from their son’s clothes may help reduce this transfer of testosterone.