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Can Progesterone Improve Hair Regrowth?

First Published Sep 18 2024
Last Updated Oct 29 2024
Pharmaceutical
Researched & Written By:
Sarah King, PhD
Reviewed By:
Rob English, Medical Editor
Can Progesterone Improve Hair Regrowth?

Article Summary

Progesterone is a hormone that plays a vital role in female reproductive health. Deficiencies in progesterone have been linked to hair thinning, particularly in conditions like female pattern hair loss (FPHL) and postpartum telogen effluvium (PPTE). While natural progesterone seems to have 5-alpha-reductase (5-AR) inhibiting properties and might help counteract androgen-driven hair loss, synthetic progesterone might, under some circumstances, increase androgen activity. So what role does progesterone play in hair loss, and how might it improve hair loss outcomes? This article explores the science to uncover evidence-based considerations.

Full Article

Progesterone is a steroid hormone with a wide range of physiological and medical effects. It is linked to female fertility and pregnancy, and it plays roles in neuro- and immunoprotection and various gynecological treatments. Studies have linked changes in progesterone levels to androgenic alopecia and postpartum telogen effluvium. Still, mixed evidence, limited research, and potential side effects have led to this treatment not being widely adopted.

In this article, we will explore the association between progesterone and hair loss, particularly female pattern hair loss (FPHL), and determine whether supplementation with progesterone can improve hair loss outcomes.

Key Takeaways

  • What Is It? Progesterone is a steroid hormone that is essential for a wide range of physiological processes. Deficiencies are associated with menstrual irregularities, fertility and pregnancy issues, mood and sleep disturbance, and physical symptoms. Other signs can include dry skin and thinning hair.
  • Evidence Quality: The evidence quality is 31/100 based on our metrics.
  • Clinical Data: There is very limited evidence supporting using progesterone to improve hair loss outcomes.
    • Study 1: 10 male patients with AGA were treated with a lotion containing 11a-hydroxyprogesterone. Improvements were observed in the “cranial” region of the scalp but not the left temporal region.
    • Study 2: 6 male patients with AGA were treated with 100 mg of progesterone for 6 months. Improvements were observed in new hair growth and the transition from vellus to terminal hairs.
  • Dosing & Formulation Considerations: Know your progestins! Many synthetic progesterone formulations are actually androgenic in nature rather than anti-androgenic. While some have more recently been developed to behave more closely to natural progesterone, there is data lacking in their efficacy to improve hair regrowth. We recommend sticking with natural progesterone until further research is available. If you are using natural progesterone, micronized allows for better systemic absorption especially when taken orally. It is typically prescribed at 200 mg daily for 12 days per 28-day cycle. However, it has not been tested for hair loss. If you decide to use non-micronized progesterone, a topical formulation may be more beneficial as oral is heavily metabolized and, therefore, may not reach the strength needed to affect hair growth outcomes. If you decide to take synthetic progestins, you might find results with cyproterone acetate or drospirenone (Slynd); however, once again, data is limited.

What Is Progesterone?

Progesterone is an important steroid hormone that plays several key roles in the female reproductive system. It is primarily produced by the corpus luteum in the ovaries after ovulation in women. For men, progesterone is produced in smaller amounts by the adrenal glands and is associated with sperm development.[1]Nio-Kobayashi, J., Miyazaki, K., Hashiba, K., Okuda, K., Iwanaga, T. (2016). Histological analysis of arteriovenous anastomosis-like vessels established in the corpus luteum of cows during … Continue reading,[2]Mirihagelle, S., Hughes, J.R., Miller, D.J. (2022). Progesterone-induced sperm release from the oviduct sperm reservoir. Cells. 11(10). 1622. Available at: https://doi.org/10.3390/cells11101622

Figure 1. Progesterone molecule.

The association between progesterone and hair health is multifaceted, involving direct hormonal effects and indirect influences.

Studies have shown that progesterone, due to its 5-alpha-reductase (5-AR) inhibiting properties, can help balance the potentially negative effects of androgens like testosterone. When progesterone levels decline, increased conversion of testosterone to dihydrotestosterone by 5-AR can occur, leading to hair follicle miniaturization and hair thinning.[3]Grymowicz, M., Rudnicka, E., Podfigurna, A., Napierała, P., Smolarczyk, R., Smolarczyk, K., Męczekalski, B. (2020). Hormonal effects on hair follicles. International Journal of Molecular Sciences. … Continue reading

Significant hormonal changes occur in menopausal women, including a decrease in estrogen and progesterone levels. Estrogen prolongs the growing (anagen) phase of the hair follicle cycle, and progesterone indirectly supports this through its androgen-inhibiting activity. Therefore, a reduction in both estrogen and progesterone can leave menopausal women vulnerable to increased androgen levels and subsequent hair loss.

Changes in progesterone levels can also affect postpartum women. During pregnancy, progesterone levels are significantly elevated but drop sharply after childbirth. This sudden decrease in progesterone and estrogen is believed to contribute to postpartum telogen effluvium (PPTE). However, unlike the other examples mentioned above, PPTE is generally self-limiting. It occurs 2-4 months after delivery and resolves typically within 6-24 weeks (although in rare cases, it can persist up to 15 months).[4]Cleveland Clinic. (no date). Postpartum Hair Loss. Cleveland Clinic. Available at: https://my.clevelandclinic.org/health/diseases/23297-postpartum-hair-loss (Accessed: September 2024)

So, we know how progesterone deficits might lead to hair loss, but does progesterone supplementation improve hair loss outcomes?

Can Progesterone Improve Hair Loss Outcomes?

As previously mentioned, progesterone has some 5-AR inhibitory properties. However, there is limited evidence to show that it can improve hair loss outcomes.

One 1987 study treated ten male patients with AGA with a lotion containing 1% 11a-hydroxyprogesterone (a progesterone derivative) for one year, and 8 patients were treated with a control.[5]Van der Willigen, A.H., Peereboom-Wynia, J.D.R., van Joost, TH., Stolz, E. (1987). A preliminary study of the effect of 11a hydroxyprogesterone on hair growth in men suffering from androgenetic … Continue reading Those treated with the progesterone derivative showed an increase in the number of anagen hairs (45 to 51) and mean hair shaft diameter (69.6 μm to 71.6 μm) in the “cranial” region of the scalp. Further improvements were seen with reduced regressing/non-growing (catagen/telogen) hairs (46-40). Unfortunately, without images, we can’t see if these improvements led to a clinically significant outcome.

Furthermore, the study also analyzed hair counts on the left temporal side of the scalp. Here, the number of anagen hairs reduced from 67 to 62, and the number of catagen/telogen hairs increased from 21 to 30, indicating a varied response to the treatment.

Figure 2: Hair counts after topical application of a progesterone derivative.[6]Van der Willigen, A.H., Peereboom-Wynia, J.D.R., van Joost, TH., Stolz, E. (1987). A preliminary study of the effect of 11a hydroxyprogesterone on hair growth in men suffering from androgenetic … Continue reading

Another small study was conducted with 6 males with AGA, acne, and benign prostatic hyperplasia (BPH).[7]Kalinchenko, S., Nikiforov, I., Samburskaya, O. (2022). BPH, Androgenic Alopecia, and Acne – Markers of Progesterone Deficiency. Journal of the Endocrine Society. 6. 431-432. Available at: … Continue reading The participants were treated with Vitamin D and 100 mg progesterone daily for 6 months. After this period, the authors reported that the patients had reduced hair loss, new hair growth, and increased vellus transition to terminal hairs. Unfortunately, the authors didn’t report the specific values or show any photos. Furthermore, it is not possible to know if the positive effects were due to supplementing with Vitamin D.

While there is a logical reasoning behind the use of progesterone for women undergoing menopause suffering from female pattern hair loss, there is no clinical evidence demonstrating its efficacy.

Progesterone Formulations

There are a number of formulations of progesterone, but how effective might they be at improving hair loss outcomes?

Oral

Oral progesterone is typically prescribed for hormone replacement therapy (HRT). However, due to its metabolism, oral progesterone may only have limited benefits for hair loss. It undergoes extensive first-pass metabolism in the liver, leading to significant degradation of the hormone before it reaches the systemic circulation, meaning that limited amounts of the hormone may reach the scalp.[8]Coombes, Z., Plant, K., Freire, C., Basit, A.W., Butler, P., Conlan, R.S., Gonzalez, D. (2021). Progesterone metabolism by human and rat hepatic and intestinal tissue. Pharmaceutics. 13(10). 1707. … Continue reading

Topical

Topical progesterone has a few potential benefits, including:

  • Localized application
  • Fewer systemic side effects
  • Bypass first pass metabolism, so more is reaching the target area

According to one source, the most common strength of progesterone applied topically is around 2%. However, this appears to be based on clinical experience rather than published studies.[9]Roseway Labs. (2020). Topicals for Hair Loss. Roseway Labs. Available at: https://rosewaylabs.com/topicals-for-hair-loss/ (Accessed: September 2024)

Injection

While some clinics use injected progesterone combined with other treatments, like platelet-rich plasma (you can find videos of these if you search on YouTube) to treat hair thinning, there is no peer-reviewed, published clinical evidence to suggest that it improves hair loss outcomes.

Micronized

Recently, there has been interest in using micronized progesterone and its potential as a hair growth treatment. This formulation may offer improved absorption and efficacy in balancing hormone levels, potentially aiding hair growth.

Micronized progesterone is a formulation of progesterone that has been processed to create very small particles smaller than 10 μm in size. This process increases the surface area of progesterone particles, allowing for better systemic absorption, especially when taken orally.[10]Hargrove, J.T., Maxson, W.S., Wentz, A.C. (1989). Absorption of oral progesterone is influenced by vehicle and particle size. American Journal of Obstetrics and Gynecology. 161(4). 948-951. Available … Continue reading

Micronized progesterone is chemically identical to the progesterone that is naturally produced in the human body, meaning it should work similarly.[11]de Lignieres, B. (1999). Oral micronized progesterone. Clinical Therapeutics. 21(1). 41-60. Available at: https://doi.org/10.1016/S0149-2917(00)88267-3 It is currently used as an HRT for menopausal symptoms, to support pregnancy and fertility, and to treat gynecological disorders.[12]Memi, E., Pavli, P., Papagianni, M., Vrachnis, N., Mastorakos, G. (2024). Diagnostic and therapeutic use of oral micronized progesterone in endocrinology. Reviews in endocrine and metabolic … Continue reading

While we have recently been getting a lot of emails from members about micronized progesterone, there is a significant gap in the literature about its potential efficacy in treating hair loss in menopausal women or people with AGA.

Synthetic Progesterone

We have discussed natural progesterone in-depth, so let’s also examine synthetic progesterone (progestins) and how it differs from natural progesterone.

Progestins differ from natural progesterone in their chemical structure, which results in different physiological effects. Some common synthetic progestins include norethindrone, medroxyprogesterone acetate (MPA), norethisterone (NET-A), and levonorgestrel. Unlike natural progesterone, many synthetic progestins can increase androgen activity. This is critical to keep in mind when choosing whether to take progestins if you suffer from hair loss. Furthermore, progestins can cause other unwanted side effects like acne, excessive hair growth in unwanted areas, and changes in skin texture, alongside more serious increased risks such as cardiovascular events (heart attacks and strokes) and cancers.

One study published in 2017 examined the androgenic and estrogenic properties of various progestins, including MPA and NET-A. The findings indicated that these progestins bind to the androgen receptor (AR) with affinities comparable to dihydrotestosterone (DHT), suggesting that they can exert androgenic effects in vivo (in cells).[13]Louw-du Toit, R., Perkins, M.S., Hapgood, J.P., Africander, D. (2017). Comparing the androgenic and estrogenic properties of progestins used in contraception and hormone therapy. Biochemical and … Continue reading

Research on hormonal contraceptives highlighted that synthetic progestins can lead to hair loss. One review conducted on data on alopecia associated with the levonorgestrel IUD found a number of women who had the IUD implanted between 2000-2001 experienced hair loss. Furthermore, in some of these cases, when the IUD was removed, women recovered their hair loss, indicating a direct effect of levonorgestrel on hair loss for some people. Unfortunately, this study is limited in many ways, including being a retrospective study and only having 73 total reports of alopecia (in New Zealand and using World Health Organization data).[14]Paterson, H., Clifton, J., Miller, D., Ashton, J., Harrison-Woolrych, M. (2007(. Hair loss with use of the levonorgestrel intrauterine device. Contraception 76. 306-309. Available at: … Continue reading

A case study from 2002, this time conducted on a woman taking a combination low-dose oral contraceptive (norethindrone and ethinyl estradiol), found shortly after starting, she experienced hair loss, which abated when stopped.[15]Yokoyama, Y., Sato, S., Saito, Y. (2002). Alopecia related to low-dose oral contraceptives. Archives of Gynecology and Obstetrics. 47. 266-246. Available at: https://doi.org/10.1007/pl00007489

So, it seems like if you have AGA, you might want to avoid synthetic progestins. But are there exceptions to the rule? There might be.

Cyproterone Acetate

While cyproterone acetate is a progestin, it has shown potential in improving hair regrowth in women with androgenic alopecia. In a study involving 80 women with FPHL treated with either 200 mg spironolactone, 50 mg of cyproterone acetate, or 100 mg daily for 10 days per month if menopausal, 44% of those treated with cyproterone acetate experienced hair regrowth. However, another 44% saw no change, and 12% continued to lose hair. There was also no significant difference between the cyproterone acetate and spironolactone groups.[16]Sinclair, R., Wewerinke, M., Jolley, D. (2005). Treatment of female pattern hair loss with oral antiandrogens. British Journal of Dermatology. 152(3). 466-473. Available at: … Continue reading

Another study reported that 77.1% of 35 women with androgenic alopecia observed hair regrowth after three months of treatment with the combined cyproterone acetate and ethinyl estradiol pill (2mg). 42.8% of participants had slight regrowth, 34.3% had moderate regrowth after trichoscopic assessment, and 22.8% showed no regrowth at all.[17]Coneac, A., Muresan, A., Orasan, M.S. (2014). Antiandrogenic therapy with ciproterone acetate in female patients who suffer from both androgenic alopecia and acne vulgaris. Clujul Medical. 87(4). … Continue reading

Figure 3. Effect of cyproterone acetate on hair regrowth. [18]Coneac, A., Muresan, A., Orasan, M.S. (2014). Antiandrogenic therapy with ciproterone acetate in female patients who suffer from both androgenic alopecia and acne vulgaris. Clujul Medical. 87(4). … Continue reading

A 12-month randomized trial found that cyproterone acetate was more effective than minoxidil at treating hair loss in women with signs of hyperandrogenism, which may be worth considering when considering hair loss treatments.[19]Vexiau, P., Chaspoux, C., Boudou, P., Fiet, J., Jouanique, C., Hardy, N., Reygagne, P. (2002). Effects of minoxidil 2% vs. cyproterone acetate treatment on female androgenetic alopecia: a controlled, … Continue reading

Drospirenone

Drospirenone (also known under the brand name Slynd) is a newer synthetic progesterone that has a unique profile. It is derived from spironolactone, a drug you may be familiar with, as it also has anti-androgenic properties. Like cyproterone acetate, Slynd does not increase androgenic activity. Instead, it has androgenic properties similar to natural progesterone, which makes it an attractive potential treatment.[20]Regidor, P.A., Mueller, A., Mayr, M. (2023). Pharmacological and metabolic effects of drospirenone as a progestin-only pill compared to combined formulations with estrogen. Womens Health (Lond). 19. … Continue reading

However, the data on hair loss is limited. One study evaluated the efficacy of oral finasteride therapy combined with an oral contraceptive containing drosperinone and ethinyl estradiol in premenopausal women with FPHL. The study found that 62% of patients showed some improvement in hair loss, but it was unclear whether the improvement was due to the higher dosage of finasteride or the combination with the oral contraceptive.[21]Iorizzo, M., Vincenzi, C., Voudouris, S., Piraccini, B.M., Tosti, A. (2006). Finasteride treatment of female pattern hair loss. Archives of Dermatology. 142(3). 298-302. Available at: … Continue reading

Furthermore, if you are sensitive or respond poorly to spironolactone, you might also experience side effects with Slynd. Another factor is that as a synthetic progestin, it might also carry elevated cardiovascular and cancer risks.

Other “new” progestins have also been developed and designed to be closer in mechanism of action to progesterone than other synthetics. These are dienogest, nestorone, nomegestrol acetate, and trimegestone, which have anti-androgenic activity, that may benefit those with hair loss, but again, they haven’t been tested.[22]Sitruk-Ware, R. (2006). New progestagens for contraceptive use. Human Reproduction Update. 12(2). 169-178. Available at: https://doi.org/10.1093/humupd/dmi046

Dosing Considerations

Oral micronized progesterone is typically prescribed at 200 mg daily for 12 days per 28-day cycle for postmenopausal women or 400 mg daily for 10 days for women who have not had a period for at least three consecutive months.[23]Memi, E., Pavli, P., Papagianni, M., Vrachnis, N., Mastorakos, G. (2024). Diagnostic and therapeutic use of oral micronized progesterone in endocrinology. Reviews in endocrine and metabolic … Continue reading It may be beneficial for women with female pattern hair loss.

Topical progesterone creams are often used in doses ranging from 20 to 40 mg, applied once or twice daily. For example, one study conducted with post-menopausal women used 40 mg daily or 20 mg twice daily for 42 days.[24]Carey, B.J., Carey, A.H., Patel, S., Carter, G., Studd, J.W. (2000). A study to evaluate serum and urinary hormone levels following short and long term administration of two regimens of progesterone … Continue reading

Injectable progesterone is injected primarily at around 150 mg every 12 weeks.[25]Nelson, A., (2002). Merits of DMPA relative to other reversible contraceptive methods. Journal of Reproductive Medicine. 47(9). 781-784. PMID: 12380406

Based on the research above, the dose for cyproterone acetate is around 50 – 100 mg, but this was given with ethinyl estradiol. For Slynd, the standard contraceptive dose of 4 mg orally once daily for 24 days followed by 4 inactive days may have potential benefits.

Dosing should be individualized based on the patient’s age, health status, and specific hormonal imbalances. Patients should report any concerning side effects to their doctor straight away. Close monitoring and adjustment of dosage by a healthcare provider are important, as effects can vary between individuals.

Best Practices

  • Premenopausal Women: Progesterone supplementation may be used to address hormonal imbalances contributing to hair thinning.
  • Postmenopausal Women: HRT with progesterone is more common, particularly in combination with estrogen, to combat hair loss linked to reduced hormone levels during menopause.
  • Individuals with Androgenic Hair Loss: Progesterone as an adjunct to other anti-androgen therapies (e.g., spironolactone) for hair loss management (if you are pre-menopausal).[26]Brough, K.R., Torgerson, R.R. (2017). Hormonal therapy in female pattern hair loss. International Journal of Women’s Dermatology.  3. 53-57. Available at: … Continue reading
  • Key Considerations: Before starting progesterone therapy, it is important to undergo individualized hormone testing and consult with a healthcare provider. Monitor for side effects such as mood changes, weight gain, or changes in menstrual patterns

Ultimately, due to the lack of evidence, we believe that steering clear of synthetic progestins, for the most part, would be best until newer data comes out supporting their use in hair growth. As it stands there may be some promising candidates, but its clear from our research that there is a gap in the evidence.

Final Thoughts

While progesterone, particularly in topical and micronized formulations, may benefit women suffering from FPHL or other hormonally influenced hair loss, more high-quality research is needed. If you are thinking about using progesterone, consult with your doctor or healthcare professional to ensure that it is tailored to your needs.

References

References
1 Nio-Kobayashi, J., Miyazaki, K., Hashiba, K., Okuda, K., Iwanaga, T. (2016). Histological analysis of arteriovenous anastomosis-like vessels established in the corpus luteum of cows during luteolysis. Journal of Ovarian Research. 9(67). 1-14. Available at: https://doi.org/10.1186/s13048-016-0277-0
2 Mirihagelle, S., Hughes, J.R., Miller, D.J. (2022). Progesterone-induced sperm release from the oviduct sperm reservoir. Cells. 11(10). 1622. Available at: https://doi.org/10.3390/cells11101622
3 Grymowicz, M., Rudnicka, E., Podfigurna, A., Napierała, P., Smolarczyk, R., Smolarczyk, K., Męczekalski, B. (2020). Hormonal effects on hair follicles. International Journal of Molecular Sciences. 21(15). 5342. Available at: https://doi.org/10.3390/ijms21155342
4 Cleveland Clinic. (no date). Postpartum Hair Loss. Cleveland Clinic. Available at: https://my.clevelandclinic.org/health/diseases/23297-postpartum-hair-loss (Accessed: September 2024)
5, 6 Van der Willigen, A.H., Peereboom-Wynia, J.D.R., van Joost, TH., Stolz, E. (1987). A preliminary study of the effect of 11a hydroxyprogesterone on hair growth in men suffering from androgenetic alopecia. Acta dermato-venereologica. 67(1). 82-85. PMID: 2436423
7 Kalinchenko, S., Nikiforov, I., Samburskaya, O. (2022). BPH, Androgenic Alopecia, and Acne – Markers of Progesterone Deficiency. Journal of the Endocrine Society. 6. 431-432. Available at: https://doi.org/10.1210/jendso/bvac150
8 Coombes, Z., Plant, K., Freire, C., Basit, A.W., Butler, P., Conlan, R.S., Gonzalez, D. (2021). Progesterone metabolism by human and rat hepatic and intestinal tissue. Pharmaceutics. 13(10). 1707. Available at: https://doi.org/10.3390/pharmaceutics13101707
9 Roseway Labs. (2020). Topicals for Hair Loss. Roseway Labs. Available at: https://rosewaylabs.com/topicals-for-hair-loss/ (Accessed: September 2024)
10 Hargrove, J.T., Maxson, W.S., Wentz, A.C. (1989). Absorption of oral progesterone is influenced by vehicle and particle size. American Journal of Obstetrics and Gynecology. 161(4). 948-951. Available at: https://doi.org/10.1016/0002-9378(89)90759-x
11 de Lignieres, B. (1999). Oral micronized progesterone. Clinical Therapeutics. 21(1). 41-60. Available at: https://doi.org/10.1016/S0149-2917(00)88267-3
12, 23 Memi, E., Pavli, P., Papagianni, M., Vrachnis, N., Mastorakos, G. (2024). Diagnostic and therapeutic use of oral micronized progesterone in endocrinology. Reviews in endocrine and metabolic disorders. 25(4). 751-772. Available at: https://doi.org/10.1007/s11154-024-09882-0
13 Louw-du Toit, R., Perkins, M.S., Hapgood, J.P., Africander, D. (2017). Comparing the androgenic and estrogenic properties of progestins used in contraception and hormone therapy. Biochemical and Biophysical Research Communications. (491)1. 140-146. Available at: https://doi.org/10.1016/j.bbrc.2017.07.063
14 Paterson, H., Clifton, J., Miller, D., Ashton, J., Harrison-Woolrych, M. (2007(. Hair loss with use of the levonorgestrel intrauterine device. Contraception 76. 306-309. Available at: https://doi.org/10.1016/j.contraception.2007.06.015
15 Yokoyama, Y., Sato, S., Saito, Y. (2002). Alopecia related to low-dose oral contraceptives. Archives of Gynecology and Obstetrics. 47. 266-246. Available at: https://doi.org/10.1007/pl00007489
16 Sinclair, R., Wewerinke, M., Jolley, D. (2005). Treatment of female pattern hair loss with oral antiandrogens. British Journal of Dermatology. 152(3). 466-473. Available at: https://doi.org/10.1111/j.1365-2133.2005.06218.x
17 Coneac, A., Muresan, A., Orasan, M.S. (2014). Antiandrogenic therapy with ciproterone acetate in female patients who suffer from both androgenic alopecia and acne vulgaris. Clujul Medical. 87(4). 226-234. Available at: https://doi.org/10.15386/cjmed-386
18 Coneac, A., Muresan, A., Orasan, M.S. (2014). Antiandrogenic therapy with ciproterone acetate in female patients who suffer from both androgenic alopecia and acne vulgaris. Clujul Medical. 87(4). 226-234. Available at: https://doi.org/10.15386/cjmed-386
19 Vexiau, P., Chaspoux, C., Boudou, P., Fiet, J., Jouanique, C., Hardy, N., Reygagne, P. (2002). Effects of minoxidil 2% vs. cyproterone acetate treatment on female androgenetic alopecia: a controlled, 12-month randomized trial. British Journal of Dermatology. 146(6). 992-999. Available at: https//doi.org/10.1046/j.1365-2133.2002.04798.x
20 Regidor, P.A., Mueller, A., Mayr, M. (2023). Pharmacological and metabolic effects of drospirenone as a progestin-only pill compared to combined formulations with estrogen. Womens Health (Lond). 19. 1-10. Available at: https://doi.org/10.1177/17455057221147388
21 Iorizzo, M., Vincenzi, C., Voudouris, S., Piraccini, B.M., Tosti, A. (2006). Finasteride treatment of female pattern hair loss. Archives of Dermatology. 142(3). 298-302. Available at: https://doi.org/10.1001/archderm.142.3.298
22 Sitruk-Ware, R. (2006). New progestagens for contraceptive use. Human Reproduction Update. 12(2). 169-178. Available at: https://doi.org/10.1093/humupd/dmi046
24 Carey, B.J., Carey, A.H., Patel, S., Carter, G., Studd, J.W. (2000). A study to evaluate serum and urinary hormone levels following short and long term administration of two regimens of progesterone creams in postmenopausal women. BJOG. 107(6). 722-726. Available at: https://doi.org/10.1111/j.1471-0528.2000.tb13331.x
25 Nelson, A., (2002). Merits of DMPA relative to other reversible contraceptive methods. Journal of Reproductive Medicine. 47(9). 781-784. PMID: 12380406
26 Brough, K.R., Torgerson, R.R. (2017). Hormonal therapy in female pattern hair loss. International Journal of Women’s Dermatology.  3. 53-57. Available at: https://doi.org/10.1016/j.ijwd.2017.01.001
Sarah King, PhD

Sarah King, PhD

Dr. Sarah King is a researcher & writer who holds a BSc in Medical Biology, an MSc in Forensic Biology, and a Ph.D. in Molecular and Cellular Biology. While at university, Dr. King’s research focused on cellular aging and senescence through NAD-dependent signaling – along with research into prostaglandins and their role in hair loss. She is a co-author on several upcoming manuscripts with the Perfect Hair Health team.

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