If the coming-of-age changes you notice in your child make you wonder if the kid you still consider your “baby” is literally growing up too fast, it’s probably nothing to worry about.

“I think a lot of times parents get confusing information,” Paul Kaplowitz, MD, PhD, FAAP, told Healthline. He is an endocrinologist with the Children’s National Health System in Washington, D.C., who has studied early puberty in children.

He said that children who develop pubic hair or body odor aren’t necessarily going through puberty. Several studies suggest that the onset of breast and pubic hair development is earlier than it has been in the past.

Kaplowitz sees a lot of children whose parents rush them to the doctor when they notice these changes, but he assures them they are nothing to be alarmed about. About 90 percent of the patients he sees don’t require treatment, he noted.

“The majority of these cases are…variations that don’t require extensive testing or treatment,” Kaplowitz said.

Puberty typically starts between ages 8 and 13 in girls and ages 9 and 14 in boys.

According to a 2019 review of scientific literature, research has found that the age puberty starts has decreased by between 12 to 18 months over the last 20 years.

In fact, one 2020 review that analyzed 30 studies on puberty found that breast development in girls decreased by around 3 months per decade between 1977 and 2013.

A 2012 study where researchers surveyed 144 pediatric offices in the United States found that boys experienced signs of puberty, including genital and pubic hair growth and early testicular volumes, between 6 months to 2 years earlier than in past studies.

Another large, population-based study of girls and boys born in Denmark between 2000 and 2003 found that girls had their first periods on average 3.6 months earlier than their mothers. The researchers said that boys may also be starting puberty earlier than previous generations, though the evidence was not as strong.

Yet some early signs of development do not necessarily mean your child has started puberty, according to a 2015 report from the American Academy of Pediatrics. The report noted that the vast majority of children with signs of early puberty have typical variations in growth and development that do not require testing or treatment.

“The truth is we truly don’t know why boys and girls, girls in particular, are showing signs of sexual maturation earlier,” Kaplowitz said.

He believes that the lack of hard data makes it difficult to say that children are showing signs of puberty or going into puberty sooner than they did in the past.

Researchers have linked several factors to early puberty in children.


The age a child enters or appears to enter puberty can vary with their race. Many studies over the past couple of decades have found that African American girls experience puberty significantly earlier than white girls, according to a 2018 research review.

For example, one 1997 study surveyed 225 U.S. healthcare professionals about the sexual maturation of their patients ages 3 through 12. The researchers concluded that African American girls were more likely to have public hair and breasts than white girls at every age. For example, they found that 27.2 percent of African American girls and 6.7 percent of white girls had developed pubic hair by age 7.

The previously cited 2012 study found that African American boys were on average more likely to have genital development and pubic hair about a year earlier than non-Hispanic white and Hispanic boys.

Researchers note that there hasn’t been a lot of research to date in African Americans in order to understand the causes or implications of racial differences. Ultimately, more studies are needed.


Obesity may be contributing to some early signs of puberty. A 2021 study found that girls who had a higher body mass index (BMI) at an early age or who gained weight more quickly compared with their peers early in life were more likely to start breast development and menstruation earlier.

A 2022 study of more than 7,000 American children also found that faster gains in weight or BMI in early life were associated with earlier puberty in both boys and girls.

A 2014 study found that children who are heavier at age 5 tend to have lower levels of sex hormone-binding globulin (SHBG) throughout childhood and reach puberty sooner. The tendency was more significant in girls than in boys.

Fat tissue contains cells that produce hormones involved in sex hormone metabolism. Researchers have speculated that more fat tissue in girls could trigger estrogen production, leading to earlier signs of puberty.

Kaplowitz notes that it can also be harder to tell if a girl who is overweight has developed breasts or simply has more fat tissue in her chest area. In most cases when a parent has brought their child to him, Kaplowitz has found that breast glands have not developed.


Children’s exposure to chemicals before birth and in the first years of life has also been examined as a potential cause of early sexual maturation.

A 2018 review of studies investigated the role of endocrine-disrupting chemicals on puberty timing, including phthalates, bisphenol A (BPA), flame retardants, polychlorinated biphenyls (PCBs), and pesticides. These chemicals can bind to hormone receptors and affect how they work.

The study concluded that the research is mixed, with some chemicals appearing to result in earlier puberty and others possibly leading to delayed puberty. Because these chemicals are so present in our everyday lives, the researchers wrote that it’s difficult to figure out the effects of each individual compound.

Their conclusion echos that of another 2022 review on the effects of endocrine-disrupting chemicals on children.

If your child is a girl under age 8 and you notice rapid growth — perhaps a few inches in a year — or progressive breast enlargement, you should consult a doctor, Kaplowitz said. Boys under age 9 who have genital enlargement should also be seen by a physician.

A child with these symptoms may be experiencing precocious puberty, which is defined as starting puberty before ages 7 to 8 in girls and age 9 in boys. Precocious puberty can lead to a reduced adult height and psychological and behavioral abnormalities, and it may require treatment.

Having some signs of early puberty doesn’t mean that your child has precocious puberty. Doctors diagnose the condition with testing, including by measuring a child’s sex hormone levels.

A doctor can also determine the cause for precocious puberty. Some variants of the condition can be caused by a other disorders, such as tumors, which can have other health repercussions.

For now, Kaplowitz wants parents to know what to look for in the event their child could have a serious concern. He also wants to remind them not to worry if they notice certain changes.

“Early pubic hair and body odor does not mean the child is actually in puberty and does not mean the child is going to start their puberty early,” Kaplowitz said.