What to Know About Puberty Starting Earlier

Puberty is a years-long process when the body transitions from childhood to adulthood. In girls, it usually starts after age 8, and in boys after age 9 — but experts are noticing that puberty is starting at younger ages.

“When puberty starts before the average age, it’s called precocious puberty,” says Dr. Aviva Sopher, a pediatric endocrinologist at NewYork-Presbyterian Morgan Stanley Children’s Hospital and associate professor of pediatrics at Columbia University Vagelos College of Physicians and Surgeons. “What we’re seeing in our offices, and what the research is showing, is a slight increase in cases of precocious puberty. This has implications for a child’s health in the short and long term and needs to be addressed.”

Here, Dr. Sopher shares the facts about precocious puberty, why it is becoming more common, and what parents need to know.

What causes puberty?
Dr. Sopher: The onset of puberty is controlled by a protein called kisspeptin, which stimulates the hypothalamus, a part of the brain, to release the hormones that get puberty started. During puberty, young people have growth spurts, their genital organs mature, and they develop physical characteristics specific to each sex.

In girls, breast development is usually the first sign of puberty, and other changes include pubic and body hair, acne, body odor and vaginal discharge. In boys, the first sign is usually testicular enlargement. Boys may also develop acne, pubic and body hair, voice deepening, and penile enlargement.

How is precocious puberty diagnosed?
The first step is a basic physical exam by a pediatrician or pediatric endocrinologist. To confirm the diagnosis, other tests may be ordered – for example, an x-ray of the child’s hand to check how their bones are maturing and blood work to look at hormone levels. For girls, a pelvic ultrasound can be performed to look for growth in the ovaries and uterus. And an MRI of the brain is frequently ordered to rule out any tumors or brain abnormalities as the cause.

Is there a rise in precocious puberty?
In general, puberty is occurring earlier. An analysis of international studies from 1977 to 2013 showed girls started puberty about three months earlier every decade or about one year earlier every 30 years.

Precocious puberty is on the rise too. For boys, research has shown a 15-fold increase in precocious puberty over the 20-year period from 1998 to 2017. In 1968, the average age of voice break was age 15; in 2019, it was age 13. The same study showed a 6-fold increase in precocious puberty in girls over the same time period.

Why is the increase happening?
Certain genes, chronic diseases, eating disorders, body weight, and excessive exercise can alter the timing of puberty. But the substantial shift in recent years could also be due to other factors. A study in Italy found an increase in new diagnoses of precocious puberty due to the COVID-19 pandemic. Another examined the impact of lifestyle changes during the lockdown on puberty, for example the use of electronic devices and the increase in stress and obesity. Certain chemicals commonly found in toothpaste, cosmetics, and other personal care products may also explain the increase in cases, especially among girls.

Are there health risks associated with precocious puberty?
We are still learning about how precocious puberty affects people later in life, but some studies do show a link to long-term health risks, including breast cancer or testicular cancer, cardiovascular diseases and obesity, metabolic disorders (such as type 2 diabetes), and shorter adult height. Further research is being conducted.

What about the mental health aspect?
Understandably, kids may feel confused, afraid, or angry if they start puberty before their peers. In addition, they may be treated differently by adults because they look older, which can lead to self-doubt and, in rare cases, a risk of sexual abuse, particularly for girls. For parents who are concerned about their child’s mental health, I recommend first speaking to the pediatrician and getting a referral to a mental health care provider.

Can precocious puberty be treated?
If puberty starts too early it may not require medical treatment, especially if puberty is not progressing rapidly. In some cases, if there is a concern a child will not be able to handle going through puberty due to their young age, or if their height prediction will be compromised, doctors can intervene with a medication to slow the process.

What would you say to parents who are concerned about their child going through precocious puberty?
Kids with precocious puberty generally do very well. It is important to complete a medical evaluation to make sure there is no underlying disorder that has to be treated. The most important thing, whether or not treatment is recommended, is regular monitoring by your pediatrician and/or a pediatric endocrinologist.

A version of this story first appeared in the Columbia University Irving Medical Center Newsroom.

Aviva Sopher, M.D., M.S., is an associate professor of pediatrics at Columbia University Vagelos College of Physicians and Surgeons and a pediatric endocrinologist at NewYork-Presbyterian Morgan Stanley Children’s Hospital with interests that include polycysytic ovary syndrome, bone health, disorders of puberty, thyroid disorders, pituitary disorders, and growth disorders. She has master of science degrees in nutrition and patient-oriented research.