Author Box
Author: Vigor Forty Editorial Team
Medically Reviewed By: Editorial Review Board
Last Updated: August 23, 2026
Medical Disclaimer
Disclaimer: This article is for informational purposes only and is not a substitute for professional medical advice, diagnosis, or treatment. Always seek the advice of your physician or other qualified health provider with any questions you may have regarding a medical condition. Consult your physician before beginning a new exercise, diet, or supplement program, especially if you have an underlying health condition or are immunocompromised. Read our full Medical Disclaimer at vigorforty.com/disclaimer.
Why Does Body Hair Grow During Puberty? Understanding Pubic and Underarm Hair Growth
Introduction
One of the most surprising moments for many mothers is noticing the first fine hairs under a daughter’s arms or along the bikini line. It often arrives before we expect it, and it can trigger questions we are not quite ready to answer: Is she starting puberty already? Why is this happening before breast development? Is this normal?
Body hair growth during puberty—known medically as adrenarche and pubarche—is a distinct biological process that often runs on a separate timeline from breast development and menstruation. While breast budding is driven by ovarian estrogen, pubic and underarm hair are driven by adrenal androgens. Understanding this separation can ease a mother’s anxiety and help her explain the changes to her daughter with confidence.
For women over 40, this topic holds special resonance. Many of us are now experiencing our own shifts in body hair due to menopause—thinning on the head, new growth on the chin. It is a reminder that hormones rule our bodies at every stage of life.
📌 Key Takeaways
- Different Hormone System: Pubic and underarm hair growth is driven by androgens from the adrenal glands, not estrogen from the ovaries.
- Can Happen Before Breast Buds: It is normal for body hair to appear before, alongside, or after breast development.
- Tanner Stages for Hair: Doctors use a separate 5-stage scale to track pubic hair growth during puberty.
- Adrenarche Is Normal: The activation of adrenal glands typically begins around age 6 to 8, with visible hair appearing by age 8 to 14.
- Premature Adrenarche: Hair growth before age 8 can be a benign variant, but it should be evaluated by a pediatrician.
- Hygiene, Not Shame: Body odor and hair are normal; teach practical hygiene without making a girl feel dirty or embarrassed.
Understanding the Biology: Adrenarche vs. Puberty
To understand why body hair grows, we need to meet a part of the body that often gets overlooked: the adrenal glands. These small triangular glands sit on top of the kidneys. They produce a variety of hormones, including cortisol, aldosterone, and androgens.
Around age 6 to 8, a process called adrenarche begins. The inner layer of the adrenal cortex starts producing increasing amounts of weak male hormones (androgens), primarily dehydroepiandrosterone (DHEA) and DHEA sulfate (DHEAS) [1].
These androgens travel through the bloodstream and stimulate hair follicles in specific areas of the body—the pubic region and the underarms—to grow thicker, darker hair. This process is called pubarche (the appearance of pubic hair).
Crucial distinction: Adrenarche is not the same as true puberty. True puberty is driven by the ovaries (thelarche for breasts, menarche for periods). Adrenarche is driven by the adrenal glands. They usually overlap, but they are separate systems.
The Tanner Stages of Pubic Hair Growth
Just as doctors use the Tanner scale for breast development, they also use a separate 5-stage scale for pubic hair growth. It is important to know this because a girl may be at Stage 3 for pubic hair but only Stage 2 for breast development. That is completely normal.
| Tanner Stage | What It Looks Like | Typical Age Range |
|---|---|---|
| Stage 1 | No pubic hair. Fine, light “peach fuzz” (vellus hair) may be present, same as on the rest of the body. | Childhood |
| Stage 2 | Sparse, straight, slightly pigmented hair appears along the labia. | 8 to 14 years |
| Stage 3 | Hair becomes darker, coarser, and curlier. It spreads sparsely across the pubic area. | 10 to 14 years |
| Stage 4 | Hair is adult-like in texture but covers a smaller area. It does not yet extend to the inner thighs. | 11 to 15 years |
| Stage 5 | Adult distribution: hair forms the classic triangular pattern and may extend to the inner thighs. | 13 to 17 years |
Note: Underarm hair usually appears about 1 to 2 years after pubic hair begins, but the sequence can vary.
Causes of Body Hair Growth During Puberty
The primary cause is the rise in adrenal androgens during adrenarche. But other hormones also play a supporting role:
- DHEA and DHEAS: These are the main adrenal androgens. They are weak compared to testosterone but strong enough to stimulate hair follicles in the pubic and axillary regions.
- Testosterone: A small amount of testosterone is produced by the ovaries and adrenal glands. It contributes to hair growth, acne, and body odor.
- Estrogen: While estrogen does not cause pubic hair growth directly, it supports the overall pubertal environment. Girls with higher estrogen often see pubic hair development accelerate once true puberty begins.
Genetic factors: The timing and amount of body hair growth is heavily influenced by genetics. If a mother developed pubic hair early or late, her daughter is likely to follow a similar pattern [2].
Symptoms: What to Expect
When adrenarche kicks in, girls may experience a cluster of changes related to androgens, not all of them about hair:
- Pubic hair growth: Fine, straight hair at first, becoming coarser and curlier over 1 to 3 years.
- Underarm hair: Usually appears after pubic hair, but can arrive simultaneously or even first in some girls.
- Body odor: The apocrine sweat glands in the underarms and groin become active. This sweat is thicker and, when broken down by skin bacteria, produces the characteristic “teenage” odor.
- Mild acne: Increased oil production can cause blackheads or pimples on the forehead, nose, and chin.
- Oily hair and scalp: Sebaceous glands become more active.
These symptoms are normal. They are not signs of disease. They simply mean the adrenal glands are doing their job.
Diagnosis: When Doctors Evaluate Body Hair
If a girl shows signs of pubic or underarm hair, a pediatrician can assess whether it is part of a normal process or a sign of an underlying issue.
What the doctor will check:
- Physical Exam: The doctor will stage the pubic hair using the Tanner scale and check for breast development. If breast buds are present alongside pubic hair, it suggests true puberty is underway.
- Medical History: The doctor will ask about the timing of hair growth, any family history of early puberty or hormonal disorders, and whether the girl has had any unusual growth spurts.
- Bone Age X-Ray: If early puberty is suspected, an X-ray of the hand and wrist can show whether the bones are maturing faster than expected. In isolated premature adrenarche, bone age is usually normal or only slightly advanced.
- Blood Tests: In cases of early or excessive hair growth, the doctor may test levels of DHEAS, testosterone, and 17-hydroxyprogesterone. Elevated testosterone may indicate polycystic ovary syndrome (PCOS) or congenital adrenal hyperplasia (CAH) [3].
Treatment and Management
For most girls, no medical treatment is needed for normal body hair growth. It is a natural part of maturation. However, management focuses on comfort and hygiene.
Hygiene Tips to Share with Your Daughter:
- Wash daily: Using a mild soap or body wash helps remove the bacteria that cause odor.
- Deodorant vs. antiperspirant: A simple deodorant masks odor; an antiperspirant reduces sweating. Both are safe for girls once odor becomes noticeable. Look for aluminum-free options if you prefer.
- Shaving: There is no medical reason to shave underarm or leg hair, but some girls request it for comfort or confidence. If she asks, teach her safe shaving techniques—using a clean razor, shaving cream, and moisturizing afterward. Alternatively, electric trimmers are safer for beginners.
- Pubic hair: Most experts advise against shaving pubic hair in young girls due to the risk of cuts, ingrown hairs, and irritation. Let it be unless there is a specific reason (like a swimsuit issue). Discuss options with your daughter when she is older.
Medical Treatment for Underlying Conditions:
If a doctor diagnoses an underlying condition like premature adrenarche that is progressing rapidly, or congenital adrenal hyperplasia, treatment may involve medications to suppress adrenal hormone production. These are managed by pediatric endocrinologists only.
Prevention and Lifestyle Factors
You cannot prevent normal body hair growth. It is programmed by genetics and hormones. However, some lifestyle habits support a healthy puberty overall:
- Maintain a healthy weight: Excess body fat can increase androgen levels in girls, potentially leading to earlier or more pronounced hair growth and acne.
- Balanced diet: A diet rich in fruits, vegetables, lean proteins, and whole grains supports steady hormone metabolism.
- Limit endocrine-disrupting chemicals: Avoid heating food in plastic, choose fragrance-free personal care products when possible, and use glass or stainless steel water bottles. Some chemicals, like phthalates, have been linked to altered pubertal timing [4].
- Encourage physical activity: Regular exercise helps regulate insulin and androgen levels, which may reduce the severity of androgen-related symptoms like acne.
When to See a Doctor
While isolated pubic hair growth is often benign, certain signs warrant a medical evaluation.
Red Flags to Watch For:
- Pubic hair before age 8: This is called premature pubarche. It is often benign, but a doctor should confirm there is no underlying adrenal problem.
- Breast development before age 8: If pubic hair and breast buds both appear very early, true precocious puberty is more likely and requires treatment to preserve adult height.
- Excessive hair growth (hirsutism): If hair appears on the face, chest, back, or abdomen in a male pattern, this suggests elevated androgens and needs investigation for PCOS or CAH.
- Severe acne: Cystic acne or acne that leaves scars is not normal in early puberty and may indicate a hormonal imbalance.
- Clitoral enlargement: This is a rare but serious sign of excess androgens. It requires immediate medical attention.
- Rapid progression: If pubic hair advances from Stage 2 to Stage 4 within a few months, or if periods begin within a year of hair onset, see a doctor.
- No pubic hair by age 14: While some girls naturally have sparse hair, complete absence by mid-teens alongside no breast development suggests delayed puberty.
The VigorForty Take
At VigorForty, we believe body hair is not a problem to be solved but a milestone to be understood. Yet we also know how loaded this topic can be. Many of us grew up with messages that body hair was “unclean” or “unfeminine.” We learned to hide it, shave it, wax it, or feel ashamed of it.
When we see our daughters begin to grow pubic and underarm hair, we have a choice: we can pass on the shame, or we can break the cycle.
What we recommend:
1. Reframe Body Hair as a Sign of Health
Explain to your daughter that this hair is a sign her adrenal glands are working. It means her body is preparing for adulthood. It is not dirty or embarrassing. It is biology.
2. Separate Hygiene from Shame
Teach her to wash her underarms and use deodorant in the same practical tone you would teach her to brush her teeth. No dramatic reactions, no “You stink!” comments. Just: “Your body is changing, so we need to update our hygiene routine.”
3. Let Her Lead on Hair Removal
If she asks to shave her legs or underarms, ask her why. Is she being teased? Does she just not like the feeling? There is no right answer. If she wants to remove hair, teach her safely. If she does not want to, support that too. The goal is body autonomy, not conformity.
4. Connect It to Your Own Journey
As women over 40, many of us are noticing unwanted facial hair, thinning scalp hair, or changes in body hair texture due to perimenopause. Use this as a teaching moment. Say, “My hormones are changing too, just in a different direction. It’s part of being a woman.” This normalizes the experience and builds empathy.
Body hair is not the enemy. Shame is. Let’s raise daughters who feel at home in their own skin.
FAQ Section
Q1: Is it normal for a 7-year-old to have pubic hair?
A: Pubic hair before age 8 is called premature pubarche. It is often a benign, isolated finding caused by early adrenal maturation. However, it should always be evaluated by a pediatrician to rule out more serious hormonal conditions.
Q2: Can a girl have pubic hair but no breast development?
A: Yes. This is quite common. Pubic hair is driven by adrenal androgens, while breast development is driven by ovarian estrogen. A girl can have Stage 3 pubic hair and still have no breast buds for another year or two. This is normal.
Q3: Does body hair growth mean she will get her period soon?
A: Not necessarily. The first period usually follows breast development by 2 to 3 years, not pubic hair onset. Pubic hair can appear years before the first period.
Q4: Is it safe for my 10-year-old to use deodorant?
A: Yes. Over-the-counter deodorants and antiperspirants are safe for children when body odor becomes noticeable. If you prefer to avoid aluminum, look for natural deodorants, but know they may be less effective at controlling sweat.
Q5: Should I let my daughter shave her pubic hair?
A: Most pediatricians advise against pubic hair removal in young girls due to the high risk of cuts, ingrown hairs, and skin irritation. There is no medical need to remove it. If she is concerned about hair visible in a swimsuit, a trimmer or trimming the edges is safer than shaving.
Q6: What is the difference between adrenarche and puberty?
A: Adrenarche is the activation of the adrenal glands, which produces androgens leading to pubic hair, underarm hair, body odor, and acne. Puberty is the activation of the ovaries, leading to breast development and menstruation. They are separate systems that often overlap.
Q7: Why does my daughter have more body hair than I did at her age?
A: Genetics play a major role, but body weight and environmental factors can also influence androgen levels. The timing and amount of hair growth vary widely among healthy girls. If you are concerned about excessive hair, especially on the face or chest, see a doctor.
Conclusion
Body hair growth during puberty is one of those topics that can feel awkward at first but becomes deeply reassuring once you understand the biology. It is a sign that the body is maturing on schedule, driven by the quiet work of the adrenal glands.
For mothers in their 40s, this is a moment to pause and recognize the arc of womanhood. Our daughters are just beginning to feel the surge of hormones that we are now beginning to lose. It is a circle, and there is something profoundly beautiful about that.
Stay calm, stay informed, and keep the conversation open. That is the best gift you can give her—and yourself.
References
- National Institute of Child Health and Human Development. (2021). Puberty. https://www.nichd.nih.gov/health/topics/puberty
- Mouritsen, A., Aksglaede, L., Sørensen, K., et al. (2010). The pubertal transition in 179 healthy Danish children: associations between pubarche, adrenarche, gonadarche, and body composition. European Journal of Endocrinology, 162(2), 241–248. https://doi.org/10.1530/EJE-09-0617
- Mayo Clinic. (2023). Premature adrenarche. https://www.mayoclinic.org/diseases-conditions/premature-adrenarche/symptoms-causes/syc-20373933
- Cleveland Clinic. (2023). Puberty: What’s normal and what’s not. https://my.clevelandclinic.org/health/articles/22193-puberty
