Short answer: New facial hair is usually caused by something common, such as PMOS (formerly PCOS), normal hormone changes around menopause or a medicine.[3], [4], [7] It needs an urgent appointment when hair appears or thickens quickly over a few months, or comes with a deeper voice, an enlarged clitoris, more muscle or male-pattern balding, because these can rarely signal a hormone-producing tumor.[1], [2], [4] Such tumors are uncommon: A 2025 expert review puts them at about 1 in 500 to 1 in 1,000 women seen for hirsutism.[2]
Noticing dark, coarse hairs on your chin or upper lip that were not there a few months ago can be unsettling, and searching online often makes it worse. The good news is that most causes are common and treatable. The aim of this article is to help you tell the usual from the unusual, so you know when a routine appointment is fine and when to push for a faster one.
PMOS, previously called polycystic ovary syndrome (PCOS), was renamed polyendocrine metabolic ovarian syndrome in May 2026.[5] If you want to check how much hair you actually have, our hirsutism self-check walks you through it.
Is sudden facial hair growth something to worry about?
Usually not, but the speed matters. A 2025 expert review in the Journal of Clinical Endocrinology and Metabolism says hirsutism that starts around puberty and progresses slowly over several years is typical of PMOS or idiopathic hirsutism, while “rapid progression” of hair growth in a woman who had none before raises suspicion of an androgen-secreting tumor.[2] The Endocrine Society guideline names the same warning signs: A rapid pace of development or progression, and signs of virilization.[1] Virilization means male-type changes beyond hair, such as a deeper voice.
| Gradual hair growth (typical) | Sudden hair growth (red flag) | |
|---|---|---|
| When it starts | Around puberty, or slowly over years[2] | New in a woman who had little hair, often in adulthood or after menopause[2], [6] |
| How fast it changes | Slow progression over several years[2] | Noticeable change within months[1], [2] |
| Other signs | Acne, irregular periods[1] | Deeper voice, enlarged clitoris, more muscle, male-pattern balding[1], [7] |
| Typical testosterone | Normal or mildly raised[12] | Often very high, though not always[1], [12] |
| Most likely causes | PMOS, idiopathic hirsutism, non-classic congenital adrenal hyperplasia[3] | Androgen-secreting tumor, ovarian hyperthecosis after menopause, Cushing’s syndrome, androgen drugs[2], [6], [7] |
| What to do | Book a routine appointment[4] | Ask for an urgent appointment[4] |
What are the common causes of new facial hair in women?
The most common cause by far is PMOS. In a study of 950 women referred to two Italian endocrine clinics for signs of androgen excess, 72.1% had PCOS (now PMOS), 15.8% had raised androgens with no other cause, 7.6% had idiopathic hirsutism and 4.3% had non-classic congenital adrenal hyperplasia (NCAH), an inherited adrenal condition.[3] These causes usually develop gradually, but many women only notice the hair at a certain point, for example after stopping the pill or gaining weight.
Getting older and menopause
The NHS notes that most women get more facial and body hair as they get older, particularly after menopause.[4] A 2023 review explains that increased facial hair is “not uncommon” in healthy postmenopausal women, because estrogen and sex hormone-binding globulin (SHBG) fall while the ovaries keep making androgens.[6] SHBG is a protein that binds testosterone and keeps it inactive. A few new chin hairs in your 50s is usually this. Read more in hirsutism and menopause.
Stopping the pill or gaining weight
Combined birth control pills raise SHBG and lower testosterone.[12] So when you stop, androgen effects that the pill was masking can show up. Weight gain and insulin resistance do the opposite of the pill: They lower SHBG, so more testosterone is free to act on hair follicles.[18] See hirsutism after stopping birth control.
Medicines and supplements
MedlinePlus lists testosterone, danazol, anabolic steroids, DHEA, glucocorticoids, cyclosporine, minoxidil and phenytoin among the medicines that can cause unwanted hair.[7] Testosterone gel used by a partner can transfer through skin contact. Its drug information tells women to call a doctor right away if they notice hair growing in new places or acne.[8] The 2025 review also warns that some women unknowingly take androgens in supplements.[2] Anabolic steroids can cause facial hair, voice deepening, male-pattern baldness and smaller breasts.[9] See our full list of drugs that can cause hirsutism, and do not stop a prescribed medicine without talking to your doctor.
What are the red flags for sudden facial hair?
The NHS advises an urgent GP appointment if new thick, dark hair suddenly starts growing on your face and body, your voice is getting lower or your muscles are getting bigger.[4] Use this checklist. One item does not mean you have a tumor, but any of them means you should be seen promptly.
- Thick, dark hair that appeared or spread noticeably within a few months[1], [4]
- A voice that is getting deeper or hoarser[1], [4]
- An enlarged clitoris (clitoromegaly)[1]
- Muscles getting bigger without a change in exercise[1], [4]
- Thinning at the temples or crown in a male pattern[9]
- Periods that become irregular or stop, alongside the hair growth[1]
- New or worsening hair growth after menopause[11]
- Signs of Cushing’s syndrome: A round face, a fatty hump between the shoulders, wide purple stretch marks, easy bruising or weak muscles[10]
- A very high testosterone result on a blood test[12]
Read more about these signs in what is virilization?.
How rare are hormone-producing tumors?
Very rare in women with typical hirsutism. Androgen-secreting tumors of the ovary or adrenal gland made up 0.2% of the 950 women in the Italian clinic study.[3] A 2012 systematic review by the Androgen Excess and PCOS Society pooled five large series of 2,601 hirsute women and found 8 tumors (0.3%).[16] The figures are higher in women investigated after menopause, because the group is more selected.
| Group studied | How many had an androgen-secreting tumor |
|---|---|
| 950 women referred to Italian clinics for androgen excess (2006) | 0.2%[3] |
| 2,601 hirsute women in five series (2012 review) | 0.3% (8 women)[16] |
| Hirsute women seen in clinics (2025 expert review) | About 1 in 500 to 1 in 1,000[2] |
| 51 postmenopausal women referred for androgen excess, Spain (2024) | 8% (4 women) had borderline or malignant tumors[15] |
| Postmenopausal women with symptoms of androgen excess (2023 review) | 2.7% had an ovarian tumor[6] |
So even after menopause, most women with new hair growth do not have a tumor. Benign conditions such as ovarian hyperthecosis were more common in the Spanish series.[15]
What other conditions cause hair to appear quickly?
Ovarian hyperthecosis
Ovarian hyperthecosis is a benign condition in which clusters of cells in the ovaries make extra androgens.[2] It is likely the second most common cause of androgen excess after menopause, found in 9.3% of postmenopausal women investigated in one UK series.[6] Unlike a tumor, it typically causes slow development of symptoms.[6]
Cushing’s syndrome
Cushing’s syndrome means too much cortisol. The US National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) says the body-made form is rare, at about 40 to 70 cases per million people, and lists excess hair on the face, neck, chest, abdomen and thighs among its symptoms in women. The most common cause is long-term, high-dose glucocorticoid medicine.[10] See hirsutism and Cushing’s syndrome.
What tests do doctors do, and at what levels do they worry?
Expect questions first. The 2025 review stresses that it is always important to determine when the hair started and how fast it is growing, and to rule out androgen drugs, supplements or a partner’s testosterone gel.[2] The doctor will usually examine your skin, voice and, if virilization is suspected, your clitoris.[1], [2] Blood tests typically include:
- Total testosterone, ideally by liquid chromatography tandem mass spectrometry (LC-MS/MS), an accurate lab method, in the early morning[1], [2]
- DHEA sulfate (DHEAS), an adrenal androgen that is very high in some adrenal tumors[6]
- Androstenedione and 17-hydroxyprogesterone to look for NCAH and other adrenal causes[1], [14]
- Cortisol tests, such as a 24-hour urine or late-night saliva test, if Cushing’s is suspected[10]
No guideline sets a single cutoff for a tumor. These are the levels that published studies, a major reference lab and one NHS referral pathway use as signals for further tests:
| Result | Source and context |
|---|---|
| Testosterone above 200 ng/dL (about 6.9 nmol/L) | Mayo Clinic Laboratories notes that ovarian or adrenal tumors often produce levels above this, while PCOS uncommonly does[12], [17] |
| Testosterone of 5.1 nmol/L (about 147 ng/dL) or more | Threshold for androgen-producing tumors in a 2018 Mayo Clinic study of 89 women with high testosterone: 90% sensitivity, 81% specificity[13] |
| After menopause: Testosterone above 2.2 nmol/L (about 63 ng/dL) | Flagged a disease cause in postmenopausal women in the same study[13] |
| After menopause: Testosterone above 5 nmol/L | Associated with virilization; needs investigation[6] |
| DHEAS above 19 µmol/L (about 700 µg/dL) | Indication to look further for an adrenal tumor[6], [17] |
| Testosterone 6 nmol/L or more before menopause, or 3 nmol/L or more after | “Significantly elevated” in one NHS regional pathway, which also advises urgent endocrinology referral for rapid onset or virilization[19] |
Two cautions. First, the Endocrine Society notes that some tumors make only moderately excessive androgens and develop slowly, so a “not very high” result does not rule one out.[1] Second, very high results are not always tumors: In a UK study of 1,205 women, even severe testosterone excess before menopause was most often due to PCOS.[14] The 2025 review concludes that the clinical presentation is the best predictor of a tumor.[2] If a tumor is suspected, imaging usually means a transvaginal ultrasound or MRI of the ovaries and a CT scan of the adrenal glands.[6] Read more in normal testosterone levels in women and blood tests, ultrasound and other labs.
What if facial hair appears suddenly after menopause?
A few new coarse hairs on the chin are common after menopause.[4], [6] What needs checking is new hair growth that is severe or getting worse. The international PCOS guideline recommends that postmenopausal women with new-onset, severe or worsening androgen excess, including hirsutism, be investigated for androgen-secreting tumors and ovarian hyperthecosis.[11] According to a 2023 review, late onset and rapid development of virilizing symptoms suggest a tumor, while slow development is typical of hyperthecosis.[6]
Who should you see, and how quickly?
Start with your family doctor or GP. Ask for an urgent appointment if you have any red flag above, and expect a referral to an endocrinologist (a hormone specialist) if your tests or symptoms point to something other than PMOS.[4], [19] If your hair growth has been slow and steady, a routine appointment is fine, but don’t keep putting it off. In our 2019 survey of 269 women with hirsutism, the typical wait before talking to a doctor was three years among the 88 women who answered that question.[20] Our which doctor should I see tool can help you choose.
Frequently asked questions
Why am I suddenly growing chin hair?
The most common reasons are PMOS, normal hormone changes with age and menopause, stopping the pill, weight gain or a medicine.[3], [4], [7], [18] If the hair is spreading fast or comes with a deeper voice or other male-type changes, see a doctor urgently.[4]
Is sudden facial hair a sign of cancer?
Rarely. Androgen-secreting tumors, some of which are cancerous, are found in about 1 in 500 to 1 in 1,000 women seen for hirsutism.[2] Rapid onset and virilization are the main clues, so get these checked promptly.[1]
Can weight gain cause facial hair?
It can contribute. Obesity and insulin resistance lower SHBG, which leaves more testosterone free to act on hair follicles.[18] Weight gain is also common in PMOS.[11]
What testosterone level suggests a tumor in a woman?
There is no single number. Levels above about 150 to 200 ng/dL (5 to 7 nmol/L) are used as warning signs in studies and by labs, but some tumors cause only moderate rises.[1], [12], [13] How fast your symptoms appeared matters as much as the result.[2]
Can menopause cause sudden facial hair?
Menopause commonly brings a few coarse chin or lip hairs.[4], [6] New hair that is severe or worsening after menopause should be checked for ovarian hyperthecosis or, rarely, a tumor.[11]
Key takeaways
- Most new facial hair is due to PMOS, aging and menopause, the pill being stopped, weight gain or medicines.
- Hair that appears or spreads within months, or comes with a deeper voice, an enlarged clitoris, more muscle or balding, needs an urgent appointment.
- Androgen-secreting tumors are rare: About 0.2% to 0.3% of women seen for androgen excess, or 1 in 500 to 1,000 hirsute women.
- There is no single testosterone cutoff. Doctors weigh the speed of symptoms alongside levels above roughly 150 to 200 ng/dL.
- After menopause, a few chin hairs are normal, but severe or worsening hair growth should be checked.
Sources
- Martin KA, Anderson RR, Chang RJ, et al. Evaluation and Treatment of Hirsutism in Premenopausal Women: An Endocrine Society Clinical Practice Guideline. J Clin Endocrinol Metab. 2018;103(4):1233-1257. PubMed 29522147
- Azziz R, Amiri M, Bril F, et al. Approach to the Patient: Hirsutism. J Clin Endocrinol Metab. 2025;110(10):e3503-e3519. PubMed 40200552
- Carmina E, Rosato F, Jannì A, Rizzo M, Longo RA. Extensive clinical experience: relative prevalence of different androgen excess disorders in 950 women referred because of clinical hyperandrogenism. J Clin Endocrinol Metab. 2006;91(1):2-6. PubMed 16263820
- NHS. Excessive hair growth (hirsutism). Accessed October 2026. Link
- Teede HJ, Bahri Khomami M, Morman R, et al. Polyendocrine metabolic ovarian syndrome, the new name for polycystic ovary syndrome: a multistep global consensus process. Lancet. 2026;407(10545):2329-2339. Published online May 12, 2026. PubMed 42119588
- Hirschberg AL. Approach to Investigation of Hyperandrogenism in a Postmenopausal Woman. J Clin Endocrinol Metab. 2023;108(5):1243-1253. PubMed 36409990
- MedlinePlus Medical Encyclopedia. Excessive or unwanted hair in women. Accessed October 2026. Link
- MedlinePlus Drug Information. Testosterone Topical. Accessed October 2026. Link
- MedlinePlus. Anabolic Steroids. Accessed October 2026. Link
- National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK). Cushing’s Syndrome. Accessed October 2026. Link
- Teede HJ, Tay CT, Laven JJE, et al. Recommendations From the 2023 International Evidence-based Guideline for the Assessment and Management of Polycystic Ovary Syndrome. J Clin Endocrinol Metab. 2023;108(10):2447-2469. PubMed 37580314
- Mayo Clinic Laboratories. TGRP: Testosterone, Total and Free, Serum (clinical information and interpretation). Accessed October 2026. Link
- Sharma A, Kapoor E, Singh RJ, et al. Diagnostic Thresholds for Androgen-Producing Tumors or Pathologic Hyperandrogenism in Women by Use of Total Testosterone Concentrations Measured by Liquid Chromatography-Tandem Mass Spectrometry. Clin Chem. 2018;64(11):1636-1645. PubMed 30068692
- Elhassan YS, Idkowiak J, Smith K, et al. Causes, Patterns, and Severity of Androgen Excess in 1205 Consecutively Recruited Women. J Clin Endocrinol Metab. 2018;103(3):1214-1223. DOI 10.1210/jc.2017-02426
- Luque Ramírez M. Postmenopausal onset of androgen excess: a diagnostic and therapeutic algorithm based on extensive clinical experience. J Endocrinol Invest. 2024;47(8):2007-2020. PubMed 38349517
- Escobar-Morreale HF, Carmina E, Dewailly D, et al. Epidemiology, diagnosis and management of hirsutism: a consensus statement by the Androgen Excess and Polycystic Ovary Syndrome Society. Hum Reprod Update. 2012;18(2):146-170. PubMed 22064667
- Mayo Clinic Laboratories. International System of Units (SI) Conversion. Accessed October 2026. Link
- MedlinePlus Medical Tests. SHBG Blood Test. Accessed October 2026. Link
- NHS Bristol, North Somerset and South Gloucestershire Integrated Care Board. Remedy: Hirsutism (adult endocrinology referral guidance). Accessed October 2026. Link
- myHirsutism. Hirsutism Survey 2019: results from 269 women with hirsutism. Published October 2026. myhirsutism.com/hirsutism-survey-results/
This article is for education and is not medical advice. Talk to a doctor about diagnosis and treatment.