Hair regrowth for women: what you need to know
Clinically reviewed by
Finasteride is currently the most effective FDA-approved pharmaceutical for treating androgenetic alopecia (AGA), but it's not a universal solution for pattern hair loss. For women experiencing female pattern hair loss, the causes of thinning hair and how it should be treated are areas of ongoing research.
Given the psychological impact of hair loss, there is huge incentive to find safe and effective treatments for everyone. In this article, we discuss what makes female pattern hair loss unique, potential triggers for female hair loss and review current solutions for hair regrowth for women.
What is female pattern hair loss?
Female pattern hair loss (FHPL), like its male equivalent, is a hair loss disorder associated with changes in hormone levels, genetics and environmental factors. Researchers have identified some similarities in terms of the biological processes responsible for hair loss in men and women. However, there are a few key differences.
Women predisposed to FPHL typically notice changes in hair density starting at around the age of 50, but onset could be much earlier (Sinclair et al., 2011). While male pattern hair loss tends to affect the frontal hairline and top of the head, signs of female pattern hair loss are usually noticeable along the hair part. As the condition progresses, the part may appear to widen (Sinclair et al., 2011). The frontal hairline and hair at the back of the head are usually unaffected (Phillips et al., 2017).
Classifying female pattern hair loss
The Hamilton-Norwood scale is widely used to assess the severity and progression of male pattern hair loss. A female version of the scale exists, called the Ludwig scale. This scale was first developed in 1977 and later refined by Dr. Rodney Sinclair and colleagues. It more accurately describes the regions of the scalp that are affected in women.
What are the causes of hair loss in women?
There are several causes of hair loss in women, that can include dietary deficiencies, stress and excessive hair styling or treatments.
Some women with pre-existing medical conditions such as hypothyroidism, hyperthyroidism, polycystic ovarian syndrome (PCOS) or anemia (iron deficiency) may also experience shedding. This usually resolves once the underlying condition is treated.
However, in contrast to the types of hair loss identified above, FPHL is a progressive condition. It is unclear how involved male sex steroid hormones (androgens) are the development of pattern hair loss in women. But follicular miniaturization, which begins when dihydrotestosterone (DHT) binds to its receptor on hair follicles, is observed in both male and female balding. Follicular miniaturization refers to structural and growth cycle changes that lead to the replacement of mature hairs with paler, shorter and more fragile vellus hairs.
The unique pattern of FPHL has also led to theories about how differences in how hair follicles respond to androgens and the location of these follicles may help explain why only certain areas of the scalp are affected in women (Vujovic & Del Marmol, 2014). Variability in the rate at which hair follicles undergo miniaturization may be another reason why balding does not happen uniformly (Yazdabadi et al., 2008).
Estrogen and hair loss
Researchers have hypothesized that estrogens (female sex steroid hormones) may play a protective role against FPHL. This theory is strengthened by the fact that many women do not experience significant hair loss until around or after menopause, when estrogen levels naturally start to decrease.
An enzyme called cytochrome P-450-aromatase has been detected in hair follicles that are more resistant to miniaturization (Sawaya & Price, 1997). It specifically converts testosterone to estrogen, which may help keep DHT levels in check around hair follicles.
Female pattern hair loss treatment
Like male AGA, FPHL may be halted or even reversed as long as it is detected early and treatment is consistent. Medications used to treat FPHL include minoxidil, 5-alpha reductase inhibitors (e.g. finasteride), anti-androgens (e.g. spironolactone) and synthetic estrogen and progesterone. Most of these are not FDA-approved for the treatment of hair loss in women, but can be prescribed off-label by a physician.
While these agents have shown some clinical benefit to hair regrowth in women, there are often special considerations for their use in women of child-bearing potential. This is because some of these medications target androgen production and are potentially harmful to male fetal development.
Also, because it is unclear the extent to which androgens are involved in FPHL, some experts suggest combining different types of medications to achieve the best results.
Currently, the FDA has approved topical minoxidil (foam) at a concentration of 5% for the treatment of hair loss in women. The medication supports hair growth by expanding blood vessels and increasing circulation to the scalp. It may also assist in “resetting” the growth cycle of hair by promoting a longer active growth phase.
A study published in 1994 found that more than half of women who had tried topical 2% minoxidil saw evidence of decreased hair loss and mild to moderate regrowth (De Villez et al., 1994). Since minoxidil does not affect sex steroid hormones, it appears to be a reasonable option for most women. The most commonly reported side effects are local skin irritation and hypertrichosis (excessive hair growth) (Sinclair, 2017).
Another class of medications are anti-androgens. Examples include spironolactone, flutamide and cyproterone acetate. Spironolactone has never been approved to treat hair loss, but may be prescribed off-label by a physician (i.e. for an indication other than that for which it was approved).
Spironolactone competes against testosterone and DHT for access to androgen receptor sites. It may also directly interfere with the production of androgens (Sinclair et al., 2011). While this blocking action is useful in delaying progression of AGA, it may have negative effects on a developing male fetus.
Because androgens play a critical role in sexual development early on in life, women who are, or may become pregnant must exercise extreme caution when taking this class of medications.
5-alpha reductase inhibitors
Finasteride is an example of a 5-alpha reductase inhibitor. Though it is often prescribed to treat male AGA, oral finasteride has not been approved for the treatment of hair loss in women. A physician will need to assess your full medical history and review any medications you may be taking to determine if this can be prescribed off-label in your specific case.
This class of medications prevents the conversion of testosterone into DHT by blocking the action of the 5-alpha reductase enzyme. Like anti-androgenic medications, there is a risk of harm to the developing male offspring. Because of this, women who are, or may become pregnant should not take finasteride.
Additional precautionary measures include: avoiding finasteride while nursing and not handling crushed tablets to minimize the risk of absorption through the skin (Iamsumang et al., 2020). It is unclear whether taking finasteride is associated with an elevated risk of breast cancer, but this is a reported potential adverse effect of taking this drug (Brough & Torgerson, 2017).
Oral contraceptives and synthetic hormones
The use of oral contraceptives to treat FPHL is currently being studied. Synthetic versions of female sex steroid hormones such as estradiol and progesterone may have a protective effect on hair follicles.
Analysis of areas of the scalp that are more resistant to balding have revealed high local levels of estradiol and aromatases, a class of enzymes that convert testosterone into estradiol) (Brough & Torgerson, 2017). Oral contraceptives work by supplementing estrogen and related hormone levels.
They have also been shown to decrease androgen levels by preventing the brain from releasing signalling hormones that would ordinarily trigger androgen production (Brough & Torgerson, 2017). Reductions in androgens levels could help stave off the development and progression of pattern hair loss.
Non-pharmacological alternatives for women experiencing hair loss include laser therapy, treatment with platelet-rich plasma (PRP) or hair transplantation (Iamsumang et al., 2020). These may be an option depending on the severity of hair loss, or if taking medication is not an option. However, you should be aware that these treatments are not universally effective, with some having stronger evidence for clinical efficacy.
In milder cases of hair loss, taking an iron supplement and maximizing scalp health by using hair care products with anti-inflammatory and antioxidant ingredients may help encourage hair growth (Hosking et al., 2019). However, these complementary treatments have not been shown to halt the progression of FPHL.
Effective treatments for hair loss shouldn’t come at the expense of safety. Although therapeutic options for AGA currently outnumber those for FPHL, the ongoing development of increasingly sophisticated formulations that prioritize the health of patients and their partners could lead to more options for hair regrowth for women in the future. If you think you might be experiencing FPHL, we recommend speaking to a physician about your symptoms.
Brough, K. R., & Torgerson, R. R. (2017, March). Hormonal therapy in female pattern hair loss. International Journal of Women’s Dermatology, 3(1), 53–57. https://doi.org/10.1016/j.ijwd.2017.01.001
Finasteride (oral ooute) precautions. (n.d.). Mayo Clinic. https://www.mayoclinic.org/drugs-supplements/finasteride-oral-route/precautions/drg-20063819
Hair loss in women: Causes, treatment & prevention. (n.d.). Cleveland Clinic. https://my.clevelandclinic.org/health/diseases/16921-hair-loss-in-women
Ho, C. H., Sood, T., & Zito, P. M. (2021). Androgenetic alopecia. StatPearls - NCBI Bookshelf. https://www.ncbi.nlm.nih.gov/books/NBK430924/
Hosking, A.-M., Juhasz, M., & Atanaskova Mesinkovska, N. (2019, February). Complementary and alternative treatments for alopecia: A comprehensive review. Skin Appendage Disorders, 72–89. https://doi.org/10.1159/000492035
Iamsumang, W., Leerunyakul, K., & Suchonwanit, P. (2020, March). Finasteride and its potential for the treatment of female pattern hair loss: Evidence to date. Drug Design, Development and Therapy, 14, 951–959. https://doi.org/10.2147/DDDT.S240615
Minoxidil oral: Uses, side effects, iteractions, pictures, warnings & dosing. (n.d.). WebMD. https://www.webmd.com/drugs/2/drug-8680/minoxidil-oral/details
Phillips, T. G. (2017). Hair loss: Common causes and treatment. American Family Physician, 96(6), 371–378. https://www.aafp.org/pubs/afp/issues/2017/0915/p371.html
Sawaya, M. E., & Price, V. H. (1997, September). Different levels of 5alpha-reductase type I and II, aromatase, and androgen receptor in hair follicles of women and men with androgenetic alopecia. Journal of Investigative Dermatology, 109(3), 296–300. https://doi.org/10.1111/1523-1747.ep12335779
Sinclair, R. D. (2017, December). Female pattern hair loss: A pilot study investigating combination therapy with low‐dose oral minoxidil and spironolactone. International Journal of Dermatology, 57(1), 104–109. https://doi.org/10.1111/ijd.13838
Sinclair, R., Patel, M., Dawson Jr, T. L., Yazdabadi, A., Yip, L., Perez, A., & Rufaut, N. W. (2011, December). Hair loss in women: Medical and cosmetic approaches to increase scalp hair fullness. British Journal of Dermatology, 165(S3), 12–18. https://doi.org/10.1111/j.1365-2133.2011.10630.x
Sinclair, R., Wewerinke, M., & Jolley, D. (2005, March). Treatment of female pattern hair loss with oral antiandrogens. British Journal of Dermatology, 152(3), 466–473. https://doi.org/10.1111/j.1365-2133.2005.06218.x
Vujovic, A., & Del Marmol, V. (2014, April). The female pattern hair loss: Review of etiopathogenesis and diagnosis. BioMed Research International. https://doi.org/10.1155/2014/767628
Yazdabadi, A., Magee, J., Harrison, S., & Sinclair, R. (2008, November). The ludwig pattern of androgenetic alopecia is due to a hierarchy of androgen sensitivity within follicular units that leads to selective miniaturization and a reduction in the number of terminal hairs per follicular unit. British Journal of Dermatology, 159(6), 1300–1302. https://doi.org/10.1111/j.1365-2133.2008.08820.x
Yip, L., Zaloumis, S., Irwin, D., Severi, G., Hopper, J., Giles, G., Harrap, S., Sinclair, R., & Ellis, J. (2009, July). Gene‐wide association study between the aromatase gene (CYP19A1) and female pattern hair loss. British Journal of Dermatology, 161(2), 289–294. https://doi.org/10.1111/j.1365-2133.2009.09186.x
Zito, P. M., Bistas, K. G., & Syed, K. (2021). Finasteride. StatPearls - NCBI Bookshelf.https://www.ncbi.nlm.nih.gov/books/NBK513329/
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