SAT398 Pubertal Status And Trends In Gender Affirming Treatment Of Transgender And Gender Diverse Youth

Disclosure: C. Lin: None. M. Oransky: None. R. Fader: None. N.R. Malhotra: None. E.M. Baldiserroto: None. C.J. Romero: None. J.D. Safer: None. M. Yau: None. Background: Transgender and gender diverse (TGD) youth seek care to affirm their gender identities and improve quality of life and mental health. Gender affirming care of youth includes pubertal assessment, pubertal suppression with gonadotropin-releasing hormone agonist (GnRHa) and gender-affirming hormone therapy (GAHT). Management choices are made collaboratively among the patient, the patient’s family, and the multidisciplinary treatment team. Objective: We sought to characterize the pubertal status of the TGD youth to consider medical intervention. Method: The medical records of 58 TGD youth referred to pediatric endocrinology from 2020-2022 were retrospectively analyzed. Pubertal assessments were made by visualization of pubic hair and breast development according to the Tanner scale and determination of testicular volume with an orchidometer. We labeled Tanner stage 1 as prepuberty; stages 2-3 as early puberty; and stages 4-5 as late puberty. Results: The median age was 15 years (range 8-18 years). 46.6% were trans girls (n=27), 44.8% were trans boys (n=26), and 8.6% were non-binary (n=1 natal male and n=4 natal female). Of the trans girls, 7.4% were prepubertal (n=2), 51.9% were in early puberty (n =14), and 40.7% were in late puberty (n=11). Of the trans boys, none were prepubertal, 3.6% were in early puberty (n=1), and 96.4% were in late puberty (n=25). Of the non-binary youth, 20% were in early puberty (n=1) and 80% were in late puberty (n=4).For the prepubertal patients, monitoring for onset of puberty without treatment was recommended. Of the 15 patients in early puberty, 73.3% started GnRHa (10 trans girls, 1 trans boy) and 26.7% started GAHT (4 trans girls). Of the 36 patients in late puberty, 2.8% received no treatment (1 trans boy), 25.0% started GnRHa (7 trans girls, 2 trans boys) and 72.2% started GAHT (4 trans girl, 22 trans boy). Of the 5 non-binary patients, 1 patient in early puberty (1 natal female) was treated with GnRHa, and 4 were in late puberty and initiated on GAHT (1 natal male, 3 natal female). Conclusion: In our multidisciplinary practice, trans feminine patients are evenly divided between those who present in early and late puberty. This presents possible implications for fertility preservation strategies. Trans masculine patients overwhelmingly present in late puberty, perhaps owing in part to earlier timing for typical “female” puberty. This means that even prompt initiation of GnRHa therapy cannot entirely prevent the potential future need for chest masculinization surgery. Presentation: Saturday, June 17, 2023