October 2024 in “Journal of the Endocrine Society” Estrogen alone can lower testosterone in some transfeminine people.
July 2025 in “Journal of Investigative Dermatology” January 2026 in “Endocrinology”
122 citations
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July 1990 in “Teratology” Finasteride exposure in pregnancy causes genital abnormalities in male rats.
3 citations
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March 2022 in “Transgender Health” More research is needed to improve lower body gender affirmation techniques.
Cyproterone slightly inhibited hair growth in castrated mice, while tamoxifen significantly inhibited hair growth in castrated mice but not in normal mice.
168 citations
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January 2005 in “Journal of Investigative Dermatology” Male and female mice have different skin thickness, and hormones affect their skin and hair growth differently.
41 citations
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November 2003 in “Annals of the New York Academy of Sciences” Male hormones, or androgens, affect women's health in areas like mood and bone density, and hormone replacement therapy using antiandrogenic progestogens can improve mood disorders and alertness in menopausal women.
5 citations
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September 2022 in “Facial Plastic Surgery & Aesthetic Medicine” Facial feminization surgery helps make facial features more feminine, improving patient satisfaction and safety.
January 2018 in “Elsevier eBooks” 5α-reductase-2 deficiency causes ambiguous genitalia at birth and affects male sexual development, but individuals often develop male characteristics at puberty.
1 citations
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August 2019 in “Environmental Toxicology” Exposure to low doses of finasteride in the womb causes changes in the prostate of both male and female gerbils.
3 citations
,
April 2019 in “Human & Experimental Toxicology” Finasteride causes harmful organ changes in female mice.
January 1983 in “Elsevier eBooks” Masculinization in affected individuals occurs gradually after puberty due to hormone changes.
19 citations
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June 2006 in “Physiology & Behavior” Finasteride slows down motherly behavior in first-time pregnant rats.
105 citations
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June 2010 in “The journal of sexual medicine” Testosterone undecanoate increases lean mass and causes various physical changes in female-to-male transsexuals.
32 citations
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July 2017 in “Clinical and Experimental Dermatology” Finasteride effectively treats hair loss in transgender men with few side effects.
9 citations
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September 1996 in “PubMed” November 2017 in “JAMA internal medicine” Women also use 5α-reductase inhibitors for hair loss and hirsutism.
98 citations
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July 1983 in “Journal of Steroid Biochemistry” Individuals with this condition often develop male traits and identities at puberty despite being raised as females.
162 citations
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April 2016 in “The Lancet Diabetes & Endocrinology” Testosterone therapy in transgender men has both desired effects like increased muscle mass and potential health risks such as higher cardiovascular risk.
Finasteride affects prostate development differently in male and female Mongolian gerbils.
1 citations
,
October 2023 in “Journal of the Endocrine Society” Testosterone treatment may affect heart response to stress in transgender men.
6 citations
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April 2019 in “Endocrinology and Metabolism Clinics of North America” Testosterone therapy for transmasculine individuals is generally safe with medical supervision, improves mental health, and has mixed effects on physical health.
17 citations
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October 1994 in “The Journal of Clinical Endocrinology and Metabolism” 9 citations
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February 2022 in “Biomedicines” Testosterone treatment may change estrogen receptor methylation in AFAB individuals.
21 citations
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July 2019 in “Cardiovascular Research” High levels of male hormones in pregnant mice cause heart enlargement and poor heart function in their female babies.
February 2024 in “Brain research bulletin” Blocking androgen activity in newborn rats affects body weight and appetite-related hormones differently in males and females.
August 2020 in “DOAJ (DOAJ: Directory of Open Access Journals)” Finasteride, at doses of 5mg or higher, may negatively affect male fertility by reducing the expression of certain genes involved in sperm production.
June 2021 in “Archives of Advances in Biosciences” Finasteride reduces sperm count and quality and alters hormone levels in mice.
10 citations
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December 2019 in “in Vivo” Testosterone makes the connections in the uterus lining simpler and lowers certain protein levels, which might lead to infertility.