Endocrine Abstracts

Introduction: We present the case of a 16-year-old woman with primary amenorrhoea and severe spinal osteoporosis from Primary Ovarian Insufficiency (POI). POI is a rare cause of primary amenorrhoea diagnosed by elevated gonadotropins on at least two occasions measured 4-6 weeks apart in women with amenorrhoea or oligomenorrhoea under the age of 40

Case report: A 16-year-old girl was referred by her general practitioner for evaluation of primary amenorrhoea. She had no history of galactorrhoea, hirsutism or visual disturbances. She had an unremarkable childhood medical history and no significant family history. Her height was 153.6 cm, weight 42.6 kg (BMI 18.1). Examination revealed delayed secondary sexual characteristics (Tanner stage 2 breasts, sparse axillary hair, Tanner stage 3 pubic hair). Genital examination revealed an intact hymen with a central opening and no evidence of outflow tract obstruction. She had central hypogonadism: FSH 114.1 IU/l, (follicular phase 3.0 - 8.1, luteal phase 1.4 - 5.5, post-menopausal 26 – 133 IU/l) and LH 25.4 IU/l (follicular phase 1.8 - 11.8, luteal phase 0.6 - 14.0, post-menopausal 5.2 - 62.0 IU/l) with low oestradiol <37 pmol/l, follicular phase 77 – 922, luteal phase 77 – 1145, post-menopausal <103 pmol/l). Thyroid function, prolactin, DHEAS, and testosterone were normal. Transvaginal ultrasound showed a normal uterus and very small ovaries without dominant follicles. Karyotype analysis revealed a 46,XX pattern, and FMR1 mutation was negative. She had no clinical features suggestive of autoimmune disease; cortisol and thyroid antibodies were negative, and ovarian antibody testing is pending. Bone densitometry revealed severe osteoporosis (Z score –4.3 at spine, –2.8 at femur, –2.9 at hip). She was commenced on hormone replacement therapy (HRT) with oestrogen patch and oral progesterone, with counselling regarding benefits and risks, particularly for bone health, and advised vitamin D supplementation alongside dietary and lifestyle optimization. Fertility counselling was provided, with discussion of future assisted reproductive options, including oocyte donation.

Discussion: This case illustrates the presentation of POI in adolescence with primary amenorrhoea and osteoporosis. The manifestation with hypergonadotrophic hypogonadism and normal genetics is consistent with idiopathic POI; autoimmune etiology has been ruled out by negative antibody results. Early hormone replacement therapy with oestrogen patches is vital to optimize bone health, support pubertal development, and reduce long-term cardiovascular risks. Ongoing psychological support and long-term follow up are important to address both medical and emotional aspects of POI.

References: 1. Meczekalski B, Niwczyk O, Bala G, Szeliga A. Managing Early Onset Osteoporosis: The Impact of Premature Ovarian Insufficiency on Bone Health. J Clin Med. 2023;12(12):4042. doi:10.3390/jcm12124042 2. Pederson, Julia & Kumar, Rajiv & Hillard, Paula & Bachrach, Laura. (2015). Primary ovarian insufficiency in adolescents: a case series. International Journal of Pediatric Endocrinology. 2015. 10.1186/s13633-015-0009-z.