{"status":"ok","message-type":"work","message-version":"1.0.0","message":{"indexed":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T12:29:28Z","timestamp":1787574568831,"version":"build-2736575974"},"reference-count":36,"publisher":"MDPI AG","issue":"16","license":[{"start":{"date-parts":[[2026,8,21]],"date-time":"2026-08-21T00:00:00Z","timestamp":1787270400000},"content-version":"vor","delay-in-days":0,"URL":"https:\/\/creativecommons.org\/licenses\/by\/4.0\/"}],"funder":[{"DOI":"10.13039\/501100018812","name":"Instituto de Investigaci\u00f3n Marqu\u00e9s de Valdecilla","doi-asserted-by":"publisher","award":["Mentoring MTVAL21\/01"],"award-info":[{"award-number":["Mentoring MTVAL21\/01"]}],"id":[{"id":"10.13039\/501100018812","id-type":"DOI","asserted-by":"publisher"}]},{"award":["Mentoring MTVAL21\/01"],"award-info":[{"award-number":["Mentoring MTVAL21\/01"]}],"id":[{"id":"https:\/\/ror.org\/025gxrt12","id-type":"ROR","asserted-by":"publisher"}]}],"content-domain":{"domain":[],"crossmark-restriction":false},"short-container-title":["J. Clin. Med.","JCM"],"abstract":"<jats:p>Objectives: This study aimed to evaluate the hormonal, hematologic, and biochemical outcomes of a conservative protocol for androgen therapy for transgender males. Methods: This was an observational, prospective, and comparative study conducted in the gender identity clinic of a tertiary university hospital. Testosterone therapy consisted of testosterone cypionate administered intramuscularly every month at an initial dosage of 25 mg\/month, which was increased to 50 mg\/month at month 3, 100 mg\/month at month 6, and 250 mg\/month at month 9. Assessments consisted of a complete blood count, biochemical tests, urine analysis, and hormonal tests. We also administered the Transgender Congruence Scale (TCS) post hoc. Results: We recruited 40 transgender males with a mean (SD) age of 22.5 (8.4) years. Only changes in the hematocrit were statistically significant as early as month 9. There were no significant changes in the biochemical parameters related to cardiovascular risk, including serum lipids, over time. There was a significant increase in total, free, and bioavailable testosterone, while SHBG levels significantly decreased; the free androgen index, urine androstanediol glucuronide, androstenedione, and prostate-specific antigen as a marker of androgenization also significantly increased over time. Among the 20 evaluable individuals, 14 (70%) scored \u22654 on the appearance congruence subscale, and 16 (80%) scored \u22654 on the gender identity subscale of the TCS. Conclusions: Our results suggest that this conservative treatment paradigm with testosterone is associated with a reduced adverse impact on hematocrit and lipids but is sufficient to achieve the gender congruence and identity acceptance desired by transgender males.<\/jats:p>","DOI":"10.3390\/jcm15166498","type":"journal-article","created":{"date-parts":[[2026,8,24]],"date-time":"2026-08-24T11:47:19Z","timestamp":1787572039000},"page":"6498","update-policy":"https:\/\/doi.org\/10.3390\/mdpi_crossmark_policy","source":"Crossref","is-referenced-by-count":0,"title":["Course of Testosterone Levels and Potential Biochemical Biomarkers of Androgenization with a Conservative Protocol of Androgen Hormone Therapy in Transgender Males"],"prefix":"10.3390","volume":"15","author":[{"ORCID":"https:\/\/orcid.org\/0000-0002-7260-3789","authenticated-orcid":false,"given":"Guillermo","family":"Velasco de Cos","sequence":"first","affiliation":[{"name":"Clinical Laboratory, Valladolid University Hospital, 47003 Valladolid, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-2531-3284","authenticated-orcid":false,"given":"Mar\u00eda Teresa","family":"Garc\u00eda Unzueta","sequence":"additional","affiliation":[{"name":"Biochemistry and Clinical Analysis Department, Marqu\u00e9s de Valdecilla University Hospital, 39008 Santander, Spain"},{"name":"Faculty of Medicine, University of Cantabria, 39005 Santander, Spain"},{"name":"Institute for Research Marqu\u00e9s de Valdecilla (IDIVAL), 39011 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Ana","family":"Moyano Mart\u00ednez","sequence":"additional","affiliation":[{"name":"Clinical Laboratory, Salamanca University Healthcare Complex, 37007 Salamanca, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0002-1387-2655","authenticated-orcid":false,"given":"Pedro","family":"Mu\u00f1oz Cacho","sequence":"additional","affiliation":[{"name":"Department of Medicina Familiar y Comunitaria (IDIVAL), 39008 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Aurelia","family":"Villar Bonet","sequence":"additional","affiliation":[{"name":"Endocrinology and Nutrition, 39008 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-8896-8611","authenticated-orcid":false,"given":"Armando Raul","family":"Guerra Ruiz","sequence":"additional","affiliation":[{"name":"Biochemistry and Clinical Analysis Department, Marqu\u00e9s de Valdecilla University Hospital, 39008 Santander, Spain"},{"name":"Institute for Research Marqu\u00e9s de Valdecilla (IDIVAL), 39011 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0001-7279-7643","authenticated-orcid":false,"given":"Bernardo A.","family":"Lavin-G\u00f3mez","sequence":"additional","affiliation":[{"name":"Biochemistry and Clinical Analysis Department, Marqu\u00e9s de Valdecilla University Hospital, 39008 Santander, Spain"},{"name":"Institute for Research Marqu\u00e9s de Valdecilla (IDIVAL), 39011 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"given":"Maialen","family":"Ormazabal Monterrubio","sequence":"additional","affiliation":[{"name":"Biochemistry and Clinical Analysis Department, Marqu\u00e9s de Valdecilla University Hospital, 39008 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]},{"ORCID":"https:\/\/orcid.org\/0000-0003-4929-4479","authenticated-orcid":false,"given":"Luis Alberto","family":"V\u00e1zquez","sequence":"additional","affiliation":[{"name":"Faculty of Medicine, University of Cantabria, 39005 Santander, Spain"},{"name":"Institute for Research Marqu\u00e9s de Valdecilla (IDIVAL), 39011 Santander, Spain"},{"name":"Department of Endocrinology, Diabetes and Nutrition, University Hospital Marqu\u00e9s de Valdecilla, 39008 Santander, Spain"}],"role":[{"vocabulary":"crossref","role":"author"}]}],"member":"1968","published-online":{"date-parts":[[2026,8,21]]},"reference":[{"key":"ref_1","doi-asserted-by":"crossref","first-page":"S1","DOI":"10.1080\/26895269.2022.2100644","article-title":"Standards of care for the health of transgender and gender diverse people, version 8","volume":"23","author":"Coleman","year":"2022","journal-title":"Int. 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