Samples were gathered as part of “fertility preservation surgery,” in which testicular tissue is harvested and preserved in hope that it will be able to produce sperm later. Every boy with gender dysphoria in the study had elected for this surgery due to inability or reluctance to ejaculate. This suggests the possible presence of various psychological and physical conditions that are unexplored in the research.

1. Murugesh V, Ritting M, Salem S, Aalam SMM, Garcia J, Chattha AJ, Zhao Y, Knapp DJ, Kalthur G, Granberg CF, Kannan N. Puberty Blocker and Aging Impact on Testicular Cell States and Function. bioRxiv [Preprint]. 2024 Mar 27:2024.03.23.586441. Doi: 10.1101/2024.03.23.586441. PMID: 38585884; PMCID: PMC10996503. ︎

The post Boys receiving puberty blockers for gender dysphoria experienced irreversible changes to their testes. appeared first on Stats for Gender.

This study was conducted from 2016 to 2021 by Dr. Johanna Olson-Kennedy. In 2024, the New York Times reported² Dr. Olson-Kennedy saying that publication of this research had been delayed because she feared that research showing that puberty blockers did not improve patients’ mental health would be “weaponized” against the use of puberty blockers by opponents of the practice. The report appeared as a pre-print, not peer-reviewed, in May 2025.

1. Johanna Olson-Kennedy, Liyuan Wang, Carolyn F. Wong, Diane Chen, Diane Ehrensaft, Marco A. Hidalgo, Amy C. Tishelman, Yee-Ming Chan, Robert Garofalo, Asa E. Radix, Stephen M. Rosenthal, Emotional Health of Transgender Youth 24 Months After Initiating Gender-Affirming Hormone Therapy, Journal of Adolescent Health, Volume 77, Issue 1, 2025, Pages 41-50, ISSN 1054-139X, https://doi.org/10.1016/j.jadohealth.2024.11.014. ︎
2. https://www.nytimes.com/2024/10/23/science/puberty-blockers-olson-kennedy.html
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The post Depression symptoms got worse in children taking puberty blockers. appeared first on Stats for Gender.

In another study² of 30 children experiencing early puberty and treated with puberty blockers, IQ fell by around seven points.

1. Wojniusz S, Callens N, Sütterlin S, Andersson S, De Schepper J, Gies I, Vanbesien J, De Waele K, Van Aken S, Craen M, Vögele C, Cools M, Haraldsen IR. Cognitive, Emotional, and Psychosocial Functioning of Girls Treated with Pharmacological Puberty Blockage for Idiopathic Central Precocious Puberty. Frontiers in Psychology. 2016 Jul 12;7:1053. doi: 10.3389/fpsyg.2016.01053. PMID: 27462292; PMCID: PMC4940404. ︎
2. Mul D, Versluis-den Bieman HJ, Slijper FM, Oostdijk W, Waelkens JJ, Drop SL. Psychological assessments before and after treatment of early puberty in adopted children. Acta Paediatrica. 2001 Sep;90(9):965-71. doi: 10.1080/080352501316978011. PMID: 11683207. ︎

The post The IQ of girls given puberty blockers for precocious puberty fell by eight points. appeared first on Stats for Gender.

The highest rate of deterioration (34%) was recorded at the 12 month evaluation, when the sample size was at its largest. Evaluations at 24 and 36 months were affected by significant loss to follow-up, which compromises the data.

1. McPherson, S., & Freedman, D. E. P. (2023). Psychological Outcomes of 12–15-Year-Olds with Gender Dysphoria Receiving Pubertal Suppression in the UK: Assessing Reliable and Clinically Significant Change. Journal of Sex & Marital Therapy, 50(3), 315–325. https://doi.org/10.1080/0092623X.2023.2281986 ︎

The post More patients on puberty blockers saw their distress deteriorate than improve. appeared first on Stats for Gender.

This study is compromised by the lack of follow-up once patients reached the age of 16, meaning there were significant effective drop-out rates at 24 and 36 months.

1. Carmichael P, Butler G, Masic U, Cole TJ, De Stavola BL, Davidson S, Skageberg EM, Khadr S, Viner RM. Short-term outcomes of pubertal suppression in a selected cohort of 12 to 15 year old young people with persistent gender dysphoria in the UK. PLoS One. 2021 Feb 2;16(2):e0243894. doi: 10.1371/journal.pone.0243894. PMID: 33529227; PMCID: PMC7853497. ︎

The post Rates of suicidality and self-harm did not improve in teenagers taking puberty blockers. appeared first on Stats for Gender.

1. Carmichael P, Butler G, Masic U, Cole TJ, De Stavola BL, Davidson S, Skageberg EM, Khadr S, Viner RM. Short-term outcomes of pubertal suppression in a selected cohort of 12 to 15 year old young people with persistent gender dysphoria in the UK. PLoS One. 2021 Feb 2;16(2):e0243894. doi: 10.1371/journal.pone.0243894. PMID: 33529227; PMCID: PMC7853497. ︎

The post The height of teenagers taking puberty blockers did not increase at an age-appropriate rate. appeared first on Stats for Gender.

This study is compromised by the lack of follow-up once patients reached the age of 16, meaning there were significant effective drop-out rates at 24 and 36 months.

1. Carmichael P, Butler G, Masic U, Cole TJ, De Stavola BL, Davidson S, Skageberg EM, Khadr S, Viner RM. Short-term outcomes of pubertal suppression in a selected cohort of 12 to 15 year old young people with persistent gender dysphoria in the UK. PLoS One. 2021 Feb 2;16(2):e0243894. doi: 10.1371/journal.pone.0243894. PMID: 33529227; PMCID: PMC7853497. ︎

The post Teenagers taking puberty blockers report more negative mood changes over time. appeared first on Stats for Gender.

This study is compromised by the lack of follow-up once patients reached the age of 16, meaning there were significant effective drop-out rates at 24 and 36 months.

1. Carmichael P, Butler G, Masic U, Cole TJ, De Stavola BL, Davidson S, Skageberg EM, Khadr S, Viner RM. Short-term outcomes of pubertal suppression in a selected cohort of 12 to 15 year old young people with persistent gender dysphoria in the UK. PLoS One. 2021 Feb 2;16(2):e0243894. doi: 10.1371/journal.pone.0243894. PMID: 33529227; PMCID: PMC7853497. ︎

The post The bone mineral density of teenagers taking puberty blockers did not increase to age-appropriate levels appeared first on Stats for Gender.

This study is compromised by the lack of follow-up once patients reached the age of 16, meaning there were significant effective drop-out rates at 24 and 36 months.

1. Carmichael P, Butler G, Masic U, Cole TJ, De Stavola BL, Davidson S, Skageberg EM, Khadr S, Viner RM. Short-term outcomes of pubertal suppression in a selected cohort of 12 to 15 year old young people with persistent gender dysphoria in the UK. PLoS One. 2021 Feb 2;16(2):e0243894. doi: 10.1371/journal.pone.0243894. PMID: 33529227; PMCID: PMC7853497. ︎

The post Puberty blockers did not improve psychological functioning of GIDS patients. appeared first on Stats for Gender.

1. Baxendale, S. (2024). The impact of suppressing puberty on neuropsychological function: A review. Acta Paediatrica, 113(7), 1156-1167. [Link] ︎

The post Puberty blockers potentially have a negative impact on neuropsychological functioning appeared first on Stats for Gender.

The 2015 Gender Identity Development Service (GIDS) statistics revealed a notably high rate of same-sex attraction among the youth seen at their clinic. Over half of the biological females reported same-sex attraction, about 20% were attracted to both sexes, and a quarter to the opposite sex, with the remaining identifying as asexual. Among biological males, approximately 30% reported same-sex attraction, another 30% to both sexes, 30% to the opposite sex, with the last 10% identifying as asexual or reporting no sexual attraction.

1. Gender Identity Development Service. (2023). Gender identity and sexuality. [Link] ︎

The post 60% of males and 70% of females attending the world’s largest gender clinic (GIDS) are same-sex attracted appeared first on Stats for Gender.

In a 2022 longitudinal study by Olson et al., 317 trans-identifying youth were followed for an average of five years after their initial social transitions (mean age at start of study = 8.1 years). The findings showed that five years post-social transition, 94% of youth continued to identify as binary transgender, 3.5% identified as nonbinary, and 2.5% identified as cisgender. Avoiding the use of the DSM-5 criteria for gender dysphoria due to ethical concerns from parents, the study classified gender identities using initial visit data, which displayed signs of gender identification and preferences, along with parent-reported “cross-sex” preferences. The final identity was then established based on the most recent interaction with the youth or their parents before January 1, 2021.

1. Olson, K. R., Durwood, L., Horton, R., Gallagher, N. M., & Devor, A. (2022). Gender identity five years after social transition. Pediatrics, 150(2). [Link] ︎

The post Social transition solidifies a transgender identity appeared first on Stats for Gender.

However, as expected, the children experienced reduced growth in height and bone strength by the time they finished their treatment at age 16.

1. Carmichael, P., Butler, G., Masic, U., Cole, T. J., De Stavola, B. L., Davidson, S., Skageberg, E. M., Khadr, S., & Viner, R. M. (2021). Short-term outcomes of pubertal suppression in a selected cohort of 12 to 15 year old young people with persistent gender dysphoria in the UK. PLOS ONE 16 (2). [Link] ︎

The post One study found that puberty blockers did not alleviate negative thoughts in children with gender dysphoria appeared first on Stats for Gender.

Adolescents who enter puberty at an older age have persistently lower bone mass density than their peers²: in one case study³, an adolescent had a bone mass density -2 standard deviations below the mean after three years of blocking puberty.

It has also been noted⁴ that:

In early-pubertal transgender youth, BMD [bone mass density] was lower than reference standards for sex designated at birth. This lower BMD may be explained, in part, by suboptimal calcium intake and decreased physical activity–potential targets for intervention.

Bone metabolism is also decreased as a result of taking cross-sex hormones, for both males and (in later life) females⁵.

1. Biggs, M. (2021). Revisiting the effect of GnRH analogue treatment on bone mineral density in young adolescents with gender dysphoria. Journal of Pediatric Endocrinology and Metabolism 34 (7): 937-939. [Link] ︎
2. Elhakeem, A., Frysz, M., Tilling, K., Tobias, J.H. & Lawlor, D.A. (2019). Association Between Age at Puberty and Bone Accrual From 10 to 25 Years of Age. JAMA Netw Open; 2(8). [Link] ︎
3. Pang, K.C., Notini, L., McDougall, R., Gillam, L., Savulescu, J., Wilkinson, D., Clark, B.A., Olson-Kennedy, J., Telfer, M.M. & Lantos, J.D. (2020). Long-term Puberty Suppression for a Nonbinary Teenager. Pediatrics 145 (2). [Link] ︎
4. Lee, J. Y., Finlayson, C., Olson-Kennedy, J., Garofalo, R., Chan, Y. M., Glidden, D. V., & Rosenthal, S. M. (2020). Low Bone Mineral Density in Early Pubertal Transgender/Gender Diverse Youth: Findings From the Trans Youth Care Study. Journal of the Endocrine Society 4 (9). [Link] ︎
5. Vlot, M.C., Wiepjes, C.M., de Jongh, R.T., T’Sjoen, G., Heijboer, A.C. & den Heijer, M. (2019). Gender-Affirming Hormone Treatment Decreases Bone Turnover in Transwomen and Older Transmen. J Bone Miner Res, 34: 1862-1872. [Link] ︎

The post Puberty blockers and cross-sex hormones negatively impact bone health in a significant number of cases appeared first on Stats for Gender.

In one study³ of 54 children referred to a clinic in childhood because of gender dysphoria and then later investigated by a follow-up study, only 21 (39%) still had gender dysphoria.

A different study⁴ of Canadian boys with gender identity disorder showed that 87.8% desisted, with only 12.2% — fewer than 1 in 8 — persisting in their transgender identity.

An ~80% desistance is not universally found⁵. Thorough investigations of the claims and counter-claims appear in two 2018 studies⁶⁷.

1. Kaltiala-Heino, R., Bergman, H., Työläjärvi, M., & Frisén, L. (2018). Gender dysphoria in adolescence: current perspectives. Adolescent health, medicine and therapeutics 9, 31–41. [Link] ︎
2. Steensma, T.D. & Cohen-Kettenis, P.T. (2011). Gender Transitioning before Puberty? Archives of Sexual Behavior 40 (4): 649-50. [Link] ︎
3. Wallien, M.S. & Cohen-Kettenis P.T. (2008) Psychosexual outcome of gender-dysphoric children. J Am Acad Child Adolesc Psychiatry 47 (12): 1413-23. [Link] ︎
4. Singh, D., Bradley, S.J. & Zucker, K.J. (2021). A Follow-Up Study of Boys With Gender Identity Disorder. Frontiers in Psychology 12. [Link] ︎
5. Temple Newhook, J., Pyne, J., Winters, K., Feder, S., Holmes, C., Tosh, J., Sinnott, M., Jamieson, A., & Picket, S. (2018). A critical commentary on follow-up studies and “desistance” theories about transgender and gender non-conforming children. International Journal of Transgenderism 19 (2). [Link] ︎
6. Steensma, T.D. & Cohen-Kettenis, P.T. (2018). A critical commentary on “A critical commentary on follow-up studies and “desistence” theories about transgender and gender non-conforming children”. International Journal of Transgenderism. [Link] ︎
7. Zucker, K. J. (2018). The myth of persistence. International Journal of Transgenderism 19 (2): 231-45. [Link] ︎

The post Gender-related distress will alleviate for around 80% of pre-teen children once they become teenagers appeared first on Stats for Gender.

Only 12% of the study participants continued to identify as transfeminine. 

1. Singh, D., Bradley, S.J. & Zucker, K.J. (2021). A Follow-Up Study of Boys With Gender Identity Disorder. Frontiers in Psychology 12. [Link] ︎

The post One study showed that, without social transition, nearly two-thirds of pre-teen gender-dysphoric males grow up to be gay or bisexual appeared first on Stats for Gender.

An excellent précis of this problem can be found in a 2018 paper³, which gives further detail:

Smith et al. report that sex reassignment is effective, based on a study of 162 adults who had undergone SRS. They were able to obtain follow-up data from only 126 (78%) of subjects because a significant number were “untraceable” or had moved abroad.

De Cuypere et al. report that sex reassignment surgery is an effective treatment for transsexuals. Of 107 patients who had undergone SRS between 1986 and 2001, 30 (28%) could not be contacted and 15 (14%) refused to participate.

Johannson et al. reported good outcomes for SRS. Of 60 patients who had undergone SRS, 42 (70%) agreed to participate in the follow up research. Of the non-participants, 1 had died of complications of SRS, 8 could not be contacted and 9 refused to participate.

Salvador et al. reported that SRS has a positive effect on psychosocial functioning. Only 55 of the 69 patients (80%) could be contacted as 17 were lost to follow-up

Van de Grift et al. reported 94–96% of patients are satisfied with SRS and have good quality of life. A total of 546 patients with Gender Dysphoria who had applied for SRS at clinics in Amsterdam, Hamburg and Ghent were contacted to complete an online survey. Only 201 (37%) responded and completed the survey. 

A good example of how this phenomenon can affect satisfaction and regret statistics comes from a 2018 paper⁴, which is often cited as proof of low regret rates. The loss to follow up rate in this paper is 36%. The authors also state:

In addition, in our population the average time to regret was 130 months, so it might be too early to examine regret rates in people who started with HT [hormonal treatment] in the past 10 years.

1. Wallien, M.S. & Cohen-Kettenis P.T. (2008) Psychosexual outcome of gender-dysphoric children. J Am Acad Child Adolesc Psychiatry 47 (12): 1413-23. [Link] ︎
2. Rauchfleisch, U., Barth, D. & Battegay, R. (1998). Resultate einer Langzeitkatamnese von Transsexuellen. Der Nervenzart 69: 799-805. [Link] ︎
3. D’Angelo, R. (2018). Psychiatry’s ethical involvement in gender-affirming care. Australasian Psychiatry 26 (5): 460-463. [Link] ︎
4. Wiepjes, C.M., Nota, N.M., de Blok, C.J.M., Klaver, M., de Vries, A.L.C., Wensing-Kruger, S.A., de Jongh, R.T., Bouman, M.B., Steensma, T.D., Cohen-Kettenis, P., Gooren, L.J.G., Kreukels, B.P.C. & den Heijer, M. (2018). The Amsterdam Cohort of Gender Dysphoria Study (1972-2015): Trends in Prevalence, Treatment, and Regrets. Journal of Sexual Medicine 15 (4). [Link] ︎

The post Studies on gender dysphoric young people often suffer from high rates of loss to follow-up – which could skew transition satisfaction rates appeared first on Stats for Gender.

1. Steensma, T.D., van der Ende, J., Verhulst, F.C. & Cohen‐Kettenis, P.T. (2013). Gender Variance in Childhood and Sexual Orientation in Adulthood: A Prospective Study. J Sex Med 10 (11): 2723-2733. [Link] ︎

The post One study found that adulthood homosexuality was 8 to 15 times higher for participants with a history of gender variance appeared first on Stats for Gender.

1. Steensma, T.D., van der Ende, J., Verhulst, F.C. & Cohen‐Kettenis, P.T. (2013). Gender Variance in Childhood and Sexual Orientation in Adulthood: A Prospective Study. J Sex Med 10 (11): 2723-2733. [Link] ︎

The post According to a long-range study, around 6% of children in the population are gender variant appeared first on Stats for Gender.

The first transgender youth clinic in the United States opened in Boston in 2007. Since then, 40 other clinics have opened that cater exclusively to children, with new clinic openings being announced frequently.

1. Marchiano, L. (2017). Outbreak: On Transgender Teens and Psychic Epidemics. Psychological Perspectives 60 (3): 345-366. [Link] ︎

The post Between 2007 and 2017, the number of transgender youth clinics in the US went from 1 to at least 41 – and the number continues to increase appeared first on Stats for Gender.