SUN-125 Osteoporosis in an Agender Adult with Low Body Weight and No Sex Hormones

Abstract Disclosure: H. Puzio: None. J.J. Chang: Medical Advisory Board for Camurus, Inc. Background: Gender-affirming care is a pivotal part of helping those with gender dysphoria become their authentic selves. Agender individuals often desire no sex hormones for affirming embodiment goals. We demonstrate how agender people may be at particular risk for osteoporosis and fragility fractures, especially when coupled with other risk factors for low bone mass. Clinical Case: A 33-year-old, agender adult (pronouns: it/its, sex assigned female at birth [AFAB]) presented to endocrine clinic for evaluation of osteoporosis. It strongly identified as having no gender and had a 10-year history of restricted eating to prevent menstrual cycles. At its lowest weight of 81 lbs (BMI 13.5 kg/m2), estimated total caloric intake was 900 kcal/day. After menarche at age 12, it later took oral contraceptives until age 27 followed by amenorrhea for the last six years. Past surgical history included bilateral mastectomy, total hysterectomy, and bilateral salpingo-oopharectomy completed just prior to clinic presentation. Initial DXA scan at age 27 showed normal bone mass (lumbar spine Z-score -1.1). Repeat DXA at age 31 demonstrated new low bone mineral density (BMD) in the lumbar spine (Z-score -3.0). DXA at age 33 showed further significant decrease in BMD in the lumbar spine (BMD change -11%, Z-score -3.8) and the mean femoral neck (BMD change -7.3%, Z-score -1.7). Labs were notable for borderline vitamin D deficiency (25 ng/mL, reference range 25-80 ng/mL). Due to the sharp decline in BMD, it was counseled on options to improve bone mass, including nutrition counseling for weight gain, hormone replacement therapy (HRT), calcium and vitamin D intake, and pharmacologic options. It declined any HRT and would only consider it if "absolutely necessary" and would prefer the option that produced the most gender-neutral physical results. Due to aversion to taking medications, it also declined bisphosphonates. It began to work with a nutritionist to regain weight now that menses were no longer possible. A few months later, it sustained a left medial femoral condyle fracture after a fall from standing height. Calcium and vitamin D intake was inconsistent. Vitamin D was low (15 ng/mL). Body weight was now 99 lbs (BMI 16.5 kg/m2). The patient was counseled again about low-dose estrogen patch, calcium and vitamin D, and zoledronic acid to assist with bone health. Ultimately, our patient continues to decline HRT but received the first dose of zoledronic acid 5 mg IV in October 2024 after vitamin D repletion. Conclusion: To our knowledge, this is the first case to describe the challenges of early osteoporosis in the care of an agender patient. Due to gender dysphoria, agender AFAB individuals may be at risk for eating disorders to prevent menses. The combination of low body weight and lack of sex steroids after gender-affirming gonadectomy may lead to fragility fractures in agender individuals. Presentation: Sunday, July 13, 2025