TurnerFertility trial: fertility preservation in young girls with Turner syndrome by freezing ovarian cortex tissue-a prospective intervention study

Abstract

Objective: To evaluate which girls with Turner syndrome (TS) could benefit from fertility preservation by ovarian tissue cryopreservation on the basis of karyotype, puberty status, and hormonal data.

Design: Prospective intervention study; participants were included between 2018 and 2020.

Setting: Tertiary hospital in the Netherlands.

Patients: In total, 106 girls with TS aged between 2 and 18 years were included. Girls with minor X chromosome deletions, Y chromosomal content, active infections, or contraindications for surgery were excluded.

Intervention: A laparoscopic unilateral ovariectomy was performed to obtain ovarian cortical tissue for cryopreservation. One tissue fragment per participant was used to determine the number of follicles per ovary by serial sectioning and staining. Chromosome analysis was performed on lymphocytes and buccal cells. A blood sample was taken before the ovariectomy for hormonal analysis.

Main outcome measures: The presence of follicles in ovarian cortex tissue from girls with TS in relation to karyotype, puberty status, and hormonal data.

Results: A unilateral ovariectomy was performed on 93 girls with TS. Complications after surgery occurred in 5 girls, including luxation of psychological symptoms in 2 girls. In 13 (14%) girls, a 46,XX cell line was found in buccal cells that was absent in lymphocytes. Follicles were observed in 30 (32%) of the 93 girls and were found mainly in girls with a 46,XX cell line in lymphocytes or buccal cells (Phi coefficient = 0.55). Spontaneous onset of puberty (Phi coefficient = 0.59), antimüllerian hormone (AMH; point-biserial correlation [r] = 0.82), inhibin B (r = 0.67), and follicle-stimulating hormone (r = -0.46) levels were also correlated strongly with the presence of follicles. Furthermore, AMH levels had a significant correlation with the number of follicles per ovary (r = 0.66).

Conclusion: Favorable predictive markers for the presence of follicles included either a 46,XX cell line, spontaneous onset of puberty, or a combination of measurable AMH and normal follicle-stimulating hormone levels. Karyotyping of two peripheral cell lines in girls with TS is recommended to reveal hidden mosaicisms. Ovarian tissue cryopreservation should be offered with caution in a research setting to those with a sufficient ovarian reserve, considering the significant loss of follicles after ovarian tissue cryopreservation and autotransplantation. Physicians should pay attention to the mental health of the girls during the whole process.

Clinical trial registration number: Trial registration number: NCT03381300- Preservation of Ovarian Cortex Tissue in Girls With Turner Syndrome - Full Text View - ClinicalTrials.gov. Registered on: December 21, 2017. First patient recruited on January 1, 2018.

Keywords: Turner syndrome; fertility preservation; ovarian tissue cryopreservation; premature ovarian failure.