P–449 Evaluation of ovarian reserve in female children and adolescents with non-iatrogenic primary ovarian insufficiency to establish criteria for ovarian tissue cryopreservation

Study question What is the predictive value of ovarian reserve evaluation in patients with non-iatrogenic primary ovarian insufficiency (NIPOI) for follicle detection in ovarian tissue harvested for cryopreservation? Summary answer Ovarian tissue cryopreservation (OTCP) should be considered if patients present at least one of the following parameters: detectable AMH, FSH≤20mIU/ml, detection of ≥ 1 antral follicle. What is known already In pre-pubertal girls suffering from NIPOI, which majorly has a genetic etiology, fertility preservation using OTCP is commonly practiced. When OTCP was performed in an unselected group of children and adolescents with NIPOI, only 26% of them had follicles in ovarian tissue while 74% did not benefit from the surgery. The role of preoperative evaluation of anti-müllerian hormone (AMH) serum level, follicular stimulating hormone (FSH) serum level, and trans-abdominal ultrasound for the antral follicle count to predict the detection of primordial follicles in the harvested ovarian tissue is unclear. Study design, size, duration We conducted a retrospective analysis of all patients ≤ 18 years old who were referred for fertility preservation counseling due to NIPOI at a single tertiary hospital between 2010 and 2020. If initial evaluation suggested a diminished ovarian reserve and at least one positive parameter indicating a follicular activity (AMH > 0.16ng/ml, FSH ≤ 20mIU/ml, detection of ≥ 1 antral follicle by transabdominal sonography), OTCP was offered. Patients with 46XY gonadal dysgenesis were excluded. Participants/materials, setting, methods OTCP was performed laparoscopically in all cases. A fresh sample of cortical tissue was fixed in buffered formaldehyde for histological analysis. The rest of the ovarian tissue was cut into small cuboidal slices 1–2 mm in thickness and cryopreserved. After the serial sections, the histological slides were evaluated for the presence of follicles by a certified pathologist. Follicles were counted and categorized as primordial, primary, and secondary. Main results and the role of chance During the study period, 39 patients with suspected NIPOI were referred to the fertility preservation center. Thirty-seven patients included in the study were diagnosed with Turner’s syndrome (n = 28), Galactosemia (n = 3), Blepharophimosis-Ptosis-Epicanthus Inversus syndrome (n = 1), and idiopathic NIPOI (n = 6). Of 28 patients with Turner’s syndrome, 6 had 45X monosomy, 15 had mosaicism and 7 had structural anomalies in X-chromosome. One patient with gonadal dysgenesis and one with the presence of Y-chromosome in 20% of somatic cells were excluded from the study. OTCP was conducted in 14 patients with at least one positive parameter suggesting ovarian function. No complications of the surgical procedure or the anesthesia were observed. Primordial follicles were found in all patients with two or three positive parameters (100%) and in three of six cases with one positive parameter (50%). In total, of the 14 patients who underwent OTCP with at least one positive parameter, 11 (79%) had primordial follicles at biopsy (mean 23.9, range 2–47). This study demonstrates a positive predictive value of 79% for the detection of primordial follicles in patients who had at least one positive parameter of ovarian reserve evaluation. If two or three parameters were positive, the positive predictive value increased to 100%. Limitations, reasons for caution This study did not examine the negative predictive value of our protocol as OTCP was not recommended in the absence of positive parameters. The future fertility potential of cryopreserved tissue in the population with NIPOI is unclear and should be discovered in further studies. Wider implications of the findings: We suggest the evaluation of ovarian reserve by antral follicles count, AMH, and FSH serum levels prior to OTCP in patients with NIPOI. By recommendation of OTCP only if ≥ 1 parameter suggesting the ovarian function is positive, unnecessary procedures can be avoided. Trial registration number Not applicable