Sebastiaan E. E. Schagen is a Dutch clinical researcher who has been involved in research and care for trans and gender diverse youth.
Background
Schagen earned a medical degree from the University of Amsterdam, then went on to specialize in pediatric endocrinology, with a particular focus on transgender healthcare. Schagen has contributed significantly to the understanding of medical treatments for gender-diverse adolescents, particularly regarding puberty suppression and gender-affirming hormone therapies.
Schagen has evaluated the safety and efficacy of gonadotropin-releasing hormone analogs (GnRH analogs) and gender-affirming hormones in adolescents. Schagen’s research focuses on the physiological and psychological effects of these treatments, contributing to the development of evidence-based guidelines for transgender healthcare.
Schagen has also written on ethics and decision-making processes in transgender healthcare, particularly concerning minors.
Selected publications by Schagen
Schagen SEE, Wouters FM, Cohen-Kettenis PT, et al. (2020). Bone development in transgender adolescents treated with GnRH analogues and subsequent gender-affirming hormones. J Clin Endocrinol Metab. 2020;105(9):e3145-e3154. doi:10.1210/clinem/dgaa393.
Schagen SEE, Brik T, Vrouenraets LJ, et al. (2018). Use of fertility preservation among a cohort of transgirls in the Netherlands. J Adolesc Health. 2019;64(5):592-595. doi:10.1016/j.jadohealth.2018.11.305.researchgate.net
Schagen SEE, Lustenhouwer P, Cohen-Kettenis PT, et al. (2018). Changes in adrenal androgens during puberty suppression and gender-affirming hormone treatment in adolescents with gender dysphoria. J Sex Med. 2018;15(9):1357-1363. doi:10.1016/j.jsxm.2018.06.010.
Schagen SEE, Hannema SE, Cohen-Kettenis PT, et al. (2017). The efficacy and safety of pubertal induction using 17beta-estradiol in transgirls. J Clin Endocrinol Metab. 2017;102(4):1222-1230. doi:10.1210/jc.2016-3684.
Schagen SEE, Cohen-Kettenis PT, Delemarre-Van de Waal HA, et al. (2016). Efficacy and safety of gonadotropin-releasing hormone agonist treatment to suppress puberty in gender dysphoric adolescents. J Sex Med. 2016;13(7):1053-1060. doi:10.1016/j.jsxm.2016.04.005.
Schagen SEE, Cohen-Kettenis PT, Delemarre-Van de Waal HA, et al. (2015). Puberty suppression and executive functioning: an fMRI-study in adolescents with gender dysphoria. Psychoneuroendocrinology. 2015;51:1-11. doi:10.1016/j.psyneuen.2014.09.016.
Schagen SEE, Bakker J, Kreukels BP, et al. (2015). Regional volumes and spatial volumetric distribution of gray matter in the gender dysphoric brain. Psychoneuroendocrinology. 2015;51:1-11. doi:10.1016/j.psyneuen.2014.09.016.
Schagen SEE, Soleman RS, Veltman DJ, et al. (2013). Sex differences in verbal fluency during adolescence: a functional magnetic resonance imaging study in gender dysphoric and control boys and girls. J Sex Med. 2013;10(2):509-516. doi:10.1111/jsm.12013.
Bui HN, Schagen SEE, Klink D, et al. (2012). Salivary testosterone in female-to-male transgender adolescents during treatment with intra-muscular injectable testosterone esters. Steroids. 2012;77(14):1501-1506. doi:10.1016/j.steroids.2012.08.008.
Schagen SEE, Heijboer AC, Bui HN, et al. (2012). Salivary testosterone in female-to-male transgender adolescents during treatment with intra-muscular injectable testosterone esters. Steroids. 2012;77(14):1501-1506. doi:10.1016/j.steroids.2012.08.008.
Schagen, S.E.E., Delemarre-van de Waal, H.A., Blanchard, R. et al. (2012). Sibling Sex Ratio and Birth Order in Early-Onset Gender Dysphoric Adolescents. Arch Sex Behav 41, 541–549 (2012). https://doi.org/10.1007/s10508-011-9777-6
Cohen-Kettenis, P. T., Schagen, S. E. E., Steensma, T. D., de Vries, A. L. C., & Delemarre-van de Waal, H. A. (2011). Puberty Suppression in a Gender-Dysphoric Adolescent: A 22-Year Follow-Up. Archives of Sexual Behavior, 40(4), 843–847. https://doi.org/10.1007/s10508-011-9758-9