Prospective evaluation of hematocrit in gender-affirming hormone treatment: results from European Network for the Investigation of Gender Incongruence

J. Defreyne, B. Vantomme, E. Van Caenegem, K. Wierckx, C. J.M. De Blok, M. Klaver, N. M. Nota, D. Van Dijk, C. M. Wiepjes, M. Den Heijer, G. T'Sjoen

Research output: Contribution to journalArticleAcademicpeer-review

Abstract

© 2018 American Society of Andrology and European Academy of Andrology. In trans persons on gender-affirming hormonal treatment, a decrease (in trans women) or increase (in trans men) in hematocrit is often observed. Reference ranges for evaluation of hematocrit levels in trans persons have not been established. This prospective cohort study is part of the European Network for the Investigation of Gender Incongruence (ENIGI). At the Ghent and Amsterdam sites, we included 625 hormone-naïve trans persons. Gender-affirming hormonal treatment was initiated at the first visit. In trans men, serum hematocrit (Hct) levels increased during the first year (+4.9 Hct %, 95% CI 3.82-5.25), with the most pronounced increase during the first 3 months (+2.7 Hct %, 95% CI 1.94-3.29). Trans men receiving testosterone esters had a larger increase in serum hematocrit levels compared to trans men receiving testosterone undecanoate (Δ 0.8 Hct %). Of 192 trans men, 22 (11.5%) developed serum hematocrit levels ≥50.0%. Trans men on testosterone undecanoate were less likely to develop hematocrit levels ≥50% or ≥52%, compared to trans men on testosterone esters, and were less likely to develop hematocrit levels ≥50%, compared to trans men on testosterone gel. In trans women, serum hematocrit had dropped by 4.1 Hct % (95% CI 3.50-4.37) after 3 months, after which only small decreases were observed. In conclusion, serum hematocrit levels can be found in the reference range of the perceived gender as from 3 months after the initiation of gender-affirming hormonal treatment.
Original languageEnglish
Pages (from-to)446-454
Number of pages9
JournalAndrology
Volume6
Issue number3
DOIs
Publication statusPublished - 1 May 2018

Cite this

@article{973fb4340c234e4994d2db25f69578b6,
title = "Prospective evaluation of hematocrit in gender-affirming hormone treatment: results from European Network for the Investigation of Gender Incongruence",
abstract = "{\circledC} 2018 American Society of Andrology and European Academy of Andrology. In trans persons on gender-affirming hormonal treatment, a decrease (in trans women) or increase (in trans men) in hematocrit is often observed. Reference ranges for evaluation of hematocrit levels in trans persons have not been established. This prospective cohort study is part of the European Network for the Investigation of Gender Incongruence (ENIGI). At the Ghent and Amsterdam sites, we included 625 hormone-na{\"i}ve trans persons. Gender-affirming hormonal treatment was initiated at the first visit. In trans men, serum hematocrit (Hct) levels increased during the first year (+4.9 Hct {\%}, 95{\%} CI 3.82-5.25), with the most pronounced increase during the first 3 months (+2.7 Hct {\%}, 95{\%} CI 1.94-3.29). Trans men receiving testosterone esters had a larger increase in serum hematocrit levels compared to trans men receiving testosterone undecanoate (Δ 0.8 Hct {\%}). Of 192 trans men, 22 (11.5{\%}) developed serum hematocrit levels ≥50.0{\%}. Trans men on testosterone undecanoate were less likely to develop hematocrit levels ≥50{\%} or ≥52{\%}, compared to trans men on testosterone esters, and were less likely to develop hematocrit levels ≥50{\%}, compared to trans men on testosterone gel. In trans women, serum hematocrit had dropped by 4.1 Hct {\%} (95{\%} CI 3.50-4.37) after 3 months, after which only small decreases were observed. In conclusion, serum hematocrit levels can be found in the reference range of the perceived gender as from 3 months after the initiation of gender-affirming hormonal treatment.",
keywords = "erythrocytosis, gender-affirming hormonal treatment, hematocrit, testosterone, transgender",
author = "J. Defreyne and B. Vantomme and {Van Caenegem}, E. and K. Wierckx and {De Blok}, {C. J.M.} and M. Klaver and Nota, {N. M.} and {Van Dijk}, D. and Wiepjes, {C. M.} and {Den Heijer}, M. and G. T'Sjoen",
year = "2018",
month = "5",
day = "1",
doi = "10.1111/andr.12485",
language = "English",
volume = "6",
pages = "446--454",
journal = "Andrology",
issn = "2047-2919",
publisher = "John Wiley and Sons Inc.",
number = "3",

}

Prospective evaluation of hematocrit in gender-affirming hormone treatment: results from European Network for the Investigation of Gender Incongruence. / Defreyne, J.; Vantomme, B.; Van Caenegem, E.; Wierckx, K.; De Blok, C. J.M.; Klaver, M.; Nota, N. M.; Van Dijk, D.; Wiepjes, C. M.; Den Heijer, M.; T'Sjoen, G.

In: Andrology, Vol. 6, No. 3, 01.05.2018, p. 446-454.

Research output: Contribution to journalArticleAcademicpeer-review

TY - JOUR

T1 - Prospective evaluation of hematocrit in gender-affirming hormone treatment: results from European Network for the Investigation of Gender Incongruence

AU - Defreyne, J.

AU - Vantomme, B.

AU - Van Caenegem, E.

AU - Wierckx, K.

AU - De Blok, C. J.M.

AU - Klaver, M.

AU - Nota, N. M.

AU - Van Dijk, D.

AU - Wiepjes, C. M.

AU - Den Heijer, M.

AU - T'Sjoen, G.

PY - 2018/5/1

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N2 - © 2018 American Society of Andrology and European Academy of Andrology. In trans persons on gender-affirming hormonal treatment, a decrease (in trans women) or increase (in trans men) in hematocrit is often observed. Reference ranges for evaluation of hematocrit levels in trans persons have not been established. This prospective cohort study is part of the European Network for the Investigation of Gender Incongruence (ENIGI). At the Ghent and Amsterdam sites, we included 625 hormone-naïve trans persons. Gender-affirming hormonal treatment was initiated at the first visit. In trans men, serum hematocrit (Hct) levels increased during the first year (+4.9 Hct %, 95% CI 3.82-5.25), with the most pronounced increase during the first 3 months (+2.7 Hct %, 95% CI 1.94-3.29). Trans men receiving testosterone esters had a larger increase in serum hematocrit levels compared to trans men receiving testosterone undecanoate (Δ 0.8 Hct %). Of 192 trans men, 22 (11.5%) developed serum hematocrit levels ≥50.0%. Trans men on testosterone undecanoate were less likely to develop hematocrit levels ≥50% or ≥52%, compared to trans men on testosterone esters, and were less likely to develop hematocrit levels ≥50%, compared to trans men on testosterone gel. In trans women, serum hematocrit had dropped by 4.1 Hct % (95% CI 3.50-4.37) after 3 months, after which only small decreases were observed. In conclusion, serum hematocrit levels can be found in the reference range of the perceived gender as from 3 months after the initiation of gender-affirming hormonal treatment.

AB - © 2018 American Society of Andrology and European Academy of Andrology. In trans persons on gender-affirming hormonal treatment, a decrease (in trans women) or increase (in trans men) in hematocrit is often observed. Reference ranges for evaluation of hematocrit levels in trans persons have not been established. This prospective cohort study is part of the European Network for the Investigation of Gender Incongruence (ENIGI). At the Ghent and Amsterdam sites, we included 625 hormone-naïve trans persons. Gender-affirming hormonal treatment was initiated at the first visit. In trans men, serum hematocrit (Hct) levels increased during the first year (+4.9 Hct %, 95% CI 3.82-5.25), with the most pronounced increase during the first 3 months (+2.7 Hct %, 95% CI 1.94-3.29). Trans men receiving testosterone esters had a larger increase in serum hematocrit levels compared to trans men receiving testosterone undecanoate (Δ 0.8 Hct %). Of 192 trans men, 22 (11.5%) developed serum hematocrit levels ≥50.0%. Trans men on testosterone undecanoate were less likely to develop hematocrit levels ≥50% or ≥52%, compared to trans men on testosterone esters, and were less likely to develop hematocrit levels ≥50%, compared to trans men on testosterone gel. In trans women, serum hematocrit had dropped by 4.1 Hct % (95% CI 3.50-4.37) after 3 months, after which only small decreases were observed. In conclusion, serum hematocrit levels can be found in the reference range of the perceived gender as from 3 months after the initiation of gender-affirming hormonal treatment.

KW - erythrocytosis

KW - gender-affirming hormonal treatment

KW - hematocrit

KW - testosterone

KW - transgender

U2 - 10.1111/andr.12485

DO - 10.1111/andr.12485

M3 - Article

VL - 6

SP - 446

EP - 454

JO - Andrology

JF - Andrology

SN - 2047-2919

IS - 3

ER -