Abstract Disclosure: F. Giusti: None. F. Marini: None. B. Weiss: Employee; Self; Amolyt. M. Ovize: Employee; Self; Amolyt. S. Benvenga: None. F. Cetani: None. A. Colao: None. S. Corbetta: Consulting Fee; Self; Italfarmaco, Abiogen, Gedeon Richter. E.C. Degli Uberti: None. M. Iacobone: None. A. Lenzi: None. G. Mantovani: None. R. Ruggeri: None. M. Brandi: Consulting Fee; Self; Alexion Pharmaceuticals, Inc., Personal Genomics, Echolight, Amolyt, Aboca, Bruno Farmaceutici, Kyowa Kirin, UCB. Speaker; Self; Abiogen, Alexion Pharmaceuticals, Inc., Monte Rosa, Amorphical, Amgen Inc, Italfarmaco, Bruno Farmaceutici, Eli Lilly & Company, Kyowa Kirin, EchoLight, Amolyt, Takeda, UCB, Menarini, Enterabio, Gedeon Richter, Theramex. The HypoparaNet database includes 509 patients with chronic hypoparathyroidism (cHP) who have been followed in 20 centers in Italy from 2014 onwards. This population is composed of 110 male and 399 female patients. cHP etiology included post-surgical n=363 (71.3%), idiopathic n=78 (15.3%) and genetic n=64 (12.6%) cases.Bone health is an important consideration in this population of patients whose skeleton is exposed both to the cHP-induced alteration of bone microarchitecture and to the progression of osteopenia/osteoporosis related to ageing, specifically in post-menopausal (or over 50 years) women.In the present cohort, dual x-ray osteodensitometry (DXA) was performed in n=173 cHP patients. We specifically assessed the prevalence of osteopenia/osteoporosis in relation to menopause (or age below or above 50 years) in female patients. Osteoporosis was defined as the presence of at least one of the measured bone sites presenting a T-score (or a Z-score for individuals < 50 years) < -2.5. Osteopenia was defined as the presence of at least one of the measured bone sites presenting a T-score (or a Z-score for individuals < 50 years) < -1.0, and all the measured bone site > -2.5. Female patients n=45 at or below 50 years (F≤50) and female patients n=97 above 50 years (F>50) had comparable mean values of albumin-adjusted serum calcium, phosphate, magnesium, PTH, 25(OH) vitamin D and 1,25(OH)2 vitamin D. The prevalence of osteopenia was high and comparable in the F≤50 and F>50 subgroups, averaging 38% and 34%, respectively. The prevalence of osteoporosis was clearly higher in the F>50 group as compared to the F≤50 group, averaging 4% and 24% respectively.These real-world data indicate that nearly half of the female patients, who represent the majority of the hypoparathyroid population, exhibit a high prevalence of osteopenia or osteoporosis that increases in relation to age. In this context, new treatment modalities (including PTH replacement therapy) for this patient population should aim at restoring a balanced bone turnover without further bone loss in order to ensure bone safety. Presentation: 6/2/2024