SAT-171 Outcomes and fertility in men with PAIS worldwide : Lessons from an I-DSD Registry platform cohort

Abstract Disclosure: M. Carré Lecoindre: None. S.F. Ahmed: None. J. Bryce: None. M. Chen: None. A. Thankamony: None. T. Guran: None. T. Sas: None. O. Hiort: None. A. Juul: None. M. Stancampiano: None. M. Cools: None. A.K. Lucas-Herald: None. P.A. Touraine: None. The androgen receptor (AR) sensitivity is an important determinant of male phenotype expression in XY individuals during fetal life and from the onset of puberty. Partial Androgen Insensitivity Syndrome (PAIS) is a spectrum of various genital phenotypes and gonadal impairments affecting approximately 1 birth in 130,000 individuals. However, there is still very little information on fertility in men with PAIS in the medical literature. Fertil’PAIS is an international, retrospective, multi-centre, observational study still in progress, evaluating fertility in PAIS men over sixteen years from the I-DSD Registry platform, as well as their genital phenotype at birth, pubertal development, psychological well-being, gender identity, and hormonal replacement therapy. Currently, 68 patients with PAIS from 11 different countries have been included, with a median age of 20.2 (16,3-69) years. Ninety-seven percent were identified as male gender, and among the 2 patients who were identified as female at birth, 1 underwent gender transition to male at 16, and 1 had a legal sex change facilitated by parents. External Genitalia Score at birth was around 8.5 out of 12: 79% had a genital tubercle beneath 30 mm, 20% no labioscrotal fusion, 55% a scrotal meatus, and 30% inguinal or impalpable gonads. Most patients had not undergone gonadectomy or gonadal biopsy and had testes identified by ultrasound. Additionally, among the 22% for whom we had information, all of them, except one, experienced spontaneous puberty at a median age of 12.7 years and 90% had gynecomastia around 13.4 years. More than 50% had high FSH, LH, AMH and total testosterone at 20 years old and we found low inhibin B in only 2 patients. Finally, we found information about fertility desire in only 39% of the 18 patients who had more than 16 years at last assessment, of whom 71% had desired fertility. Only 6 patients had sperm assessment with count - all abnormal-, none of them had sperm cryoconservation, and only one was able to father twice thanks to medically assisted conception (MAP). In conclusion, the phenotype of PAIS men at birth varies greatly, but they mostly exhibit severe variations in genital development and gynecomastia. While most undergo spontaneous puberty and have normal inhibin B levels, fertility remains poorly monitored, and cryoconservation or MAP is not well considered. Therefore, we need to obtain more information about fertility in these patients to better understand their desires and provide them with follow-up and assistance according to their needs. Presentation: Saturday, July 12, 2025