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Published on: October 25, 2024
Age-Associated Primordial Follicle Density in Human Ovarian Cortical Tissue from Post-Pubertal Females Undergoing
Murat Erden1, Soner Celik2, Kutluk H Oktay3
1Department of Obstetrics, Gynecology, and Reproductive Sciences, Yale University School of Medicine, New Haven, CT, USA; Obstetrics and Gynecology Residency Program, Creighton University East Valley Arizona, Gilbert, AZ, USA.
Objective:
To describe the age-associated distribution of primordial follicle density (PFD) in human ovarian cortical tissue from post-pubertal individuals undergoing ovarian tissue cryopreservation, with observations concentrated in the 20-34-year range.
Design:
Descriptive translational research study using log-transformed quantile regression to characterize conditional percentiles of PFD, with bootstrap resampling to assess uncertainty.
Subjects:
Ovarian cortical tissue from 33 post-pubertal individuals aged 16-43 years obtained from organ donors and patients undergoing ovarian tissue cryopreservation, without prior exposure to intensive alkylating agent-based chemotherapy.
Exposure:
Age at ovarian tissue harvesting.
Main Outcome Measures:
Age-specific distribution of PFD (follicles/mm2), modeled across the 10th, 25th, 50th, 75th, and 90th percentiles; estimates outside the 20-34-year range are exploratory owing to sparse representation.
Results:
Primordial follicle density declined nonlinearly with age, with wide interindividual variability. Within the well-represented 20-34-year range (21 of 33 individuals), the estimated median PFD decreased from 1.18 follicles/mm2 at age 20 to 0.49 follicles/mm2 at age 34. Estimates at younger (16-19 years, n=2) and older (35-43 years, n=10) ages showed substantially wider bootstrap uncertainty and should be considered exploratory. An exploratory descriptive analysis of PFD and graft duration among eight ovarian transplant recipients was also performed.
Conclusion:
This study provides a descriptive characterization of the age-associated distribution of PFD in ovarian cortical tissue prepared under contemporary fertility-preservation conditions. These findings are concentrated in the 20-34-year range and are hypothesis-generating. Larger multicenter studies linking PFD to graft function and longevity are needed before age-specific percentiles can inform individualized ovarian tissue transplantation.
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