Adrenarche

What is adrenarche?

Adrenarche (pronounced ad-dren-ARK-ee) is the natural bodily process in which your child’s adrenal glands start producing more of a hormone called dehydroepiandrosterone (DHEA). Adrenarche typically happens between 6 and 8 years of age. It begins about two years before true puberty (pubarche).

DHEA is a precursor hormone, which means your body converts it into more powerful hormones. These include androgens (testosterone and androstenedione) and estrogen. Androgens are a group of sex hormones. They help start puberty and play a role in reproductive health and body development.

Another form of DHEA is DHEAS (dehydroepiandrosterone-sulfate). This is the form that circulates in your bloodstream. Researchers know that adrenarche is happening when there’s a detectable amount of DHEAS in a blood test. But healthcare providers don’t typically order this test for children, as adrenarche is a natural and expected bodily process.

What happens during adrenarche?

During adrenarche, the adrenal cortex in your child’s adrenal glands begins to mature (develop more).

The cortex is the outer part of your adrenal gland that releases certain hormones.

It consists of three layers:

• Zona glomerulosa (outer layer).
• Zona fasciculata (middle layer).
• Zona reticularis (innermost layer). This layer matures the most in adrenarche.

With this development, your child’s adrenal glands produce DHEA, which their body turns into androgens. DHEA — and the hormones your child’s body turns them into — kick off the development and/or activity of:

• Sebaceous glands: Sebaceous glands are organs in your skin that make and secrete sebum. Sebum is a substance that provides a protective coating for your skin to help it retain moisture. It also contributes to body odor.
• Apocrine glands: These are special glands located in your underarm and genital regions. They’re inactive until they’re stimulated by the adrenal hormones in adrenarche.
• Pubic and armpit (axillary) hair: Pubic hair is darker and thicker body hair that grows in your genital region. Androgens stimulate the growth of pubic hair and armpit hair.

These adrenal hormones are different from the ones that trigger breast and penis growth during puberty (gonadarche). Gonadarche is the further development of the ovaries or testicles, which produce major sex hormones (estrogen or testosterone). These organs and hormones make sexual reproduction possible, unlike the hormones in adrenarche.

Adrenarche and gonadarche are two different and independent processes. Researchers aren’t sure what triggers the start of adrenarche.

How long does adrenarche last?

Adrenarche typically lasts about two years before pubarche (the beginning of puberty) starts. But your child’s adrenal glands continue to produce DHEA into adulthood. DHEA levels are at their highest in early adulthood (around 20 to 24 years) and then slowly fall as you age.

What are the signs of adrenarche?

There are no physical signs of when adrenarche begins. In other words, you don’t see any physical changes directly related to the initial increase in DHEA levels.

But, about two years after the start of adrenarche is pubarche — the appearance of pubic hair. Healthcare providers consider this the physical result of adrenarche. Pubarche also marks the beginning of puberty.

Other signs of pubarche include:

• Development of underarm (axillary) hair.
• Body odor (apocrine odor).
• Increased oiliness of your child’s skin and hair.
• Acne.

What age does pubic hair develop?

Studies show that the average age of pubic hair development varies slightly based on your child’s sex, race and ethnicity. The average ages for pubic hair development in the U.S. are:

• 9.5 years for non-Hispanic Black children assigned female at birth (AFAB).
• 10.3 years for Mexican-American children AFAB.
• 10.5 years for non-Hispanic white children AFAB.
• 11.1 years for non-Hispanic Black children assigned male at birth (AMAB).
• 12.3 years for Mexican-American children AMAB
• 12 years for non-Hispanic white children AMAB.

It’s important to remember that every child develops differently. Talk to your child’s pediatrician if you have any questions or concerns about their development.

What is premature adrenarche?

Premature adrenarche happens when pubic and armpit hair and body odor develop earlier than expected — typically before the age of 8 in children AFAB and 9 in children AMAB,

Premature adrenarche is technically premature pubarche. You wouldn’t know that adrenarche started earlier than usual until you see the signs of its physical manifestation: pubarche.

Children AFAB are nine times more likely to have premature adrenarche than children AMAB. Researchers aren’t sure what causes premature adrenarche.

What are the symptoms of premature adrenarche?

Symptoms of premature adrenarche include:

• Appearance of pubic and/or underarm hair in children AFAB younger than 8 or children AMAB younger than 9.
• Underarm odor (body odor), often requiring the use of deodorant.

Many children with premature adrenarche are greater than average in height — often above the 90th percentile for their age and sex.

It’s important to note that premature adrenarche doesn’t involve early breast development or penis enlargement (gonadarche). If your child has these signs as well, they most likely have precocious (early) puberty, not premature adrenarche.

How is premature adrenarche diagnosed?

If your child has signs of premature adrenarche, their pediatrician may want to make sure there’s not another condition causing the symptoms. These may include:

• Precocious puberty.
• Congenital adrenal hyperplasia.
• Exogenous (coming from outside) androgen exposure.
• Androgen-secreting tumors.

Your child’s provider will do a physical exam and may order certain blood and imaging tests. During the physical exam, the pediatrician will need to look at your child’s genital region. They’ll ask for permission (consent) before doing this.

The pediatrician may refer your child to a pediatric endocrinologist (a provider who specializes in hormones). If your child’s provider(s) can rule out all of these conditions, then your child has premature adrenarche.

About 90% of cases of early pubic hair growth are due to premature adrenarche. The other 10% of cases result from these conditions.

Is premature adrenarche dangerous?

It may be alarming to notice that your child has underarm and pubic hair earlier than expected. But premature adrenarche generally isn’t physically dangerous.

Research shows that it may mildly increase your child’s risk for:

• Obesity.
• Insulin resistance.
• Polycystic ovary syndrome (PCOS).
• Mood disorders.

However, premature adrenarche may affect your child’s mental health. Developing at a different rate than their peers can stir up feelings of shame, embarrassment and otherness. It may also put them at risk for bullying or unwanted attention. If your child’s premature adrenarche is causing them distress, consider reaching out to a mental health professional, like a child psychologist.

Is there treatment for premature adrenarche?

No treatment can stop or reverse pubic or armpit hair growth once it’s started. Medications that can slow down the progression of precocious puberty have no effect on the hormones involved in adrenarche.

Is premature adrenarche preventable?

Premature adrenarche generally isn’t preventable. But studies show that certain factors may increase your child’s risk of premature adrenarche, including:

• Low birth weight (less than 5 pounds, 8 ounces).
• Preterm birth (before 37 weeks of pregnancy).
• History of brain injury. This can increase their risk of precocious puberty, as well.

A note from Cleveland Clinic

It can be difficult to see your child transition into puberty — especially if it’s sooner than you anticipated. Know that adrenarche and pubarche are natural and totally normal processes. Premature adrenarche may be alarming, but it’s generally not physically harmful to your child. If you have any concerns about your child’s development, reach out to their healthcare provider. They can evaluate your child and determine if they’re developing as expected.