Related Experiment Video
Updated: Jul 16, 2026
Collection of Human Follicular Fluid, Follicle Somatic Cells, and Immature Oocytes from Individuals Undergoing In Vitro Fertilization
Published on: October 24, 2025
In vitro maturation of oocytes collected from unstimulated ovaries for oocyte donation
Hananel Holzer1, Eleanor Scharf, Ri-Cheng Chian
1McGill Reproductive Center, Department of Obstetrics and Gynecology, McGill University, Montreal, Quebec, Canada. hananel.holzer@muhc.mcgill.ca
Objective:
To assess the role of immature oocyte collection from unstimulated ovaries as a potential source of oocyte donation.
Design:
Prospective cohort study.
Setting:
A tertiary, university-based, in vitro fertilization center.
Patient(S):
Twelve oocyte donors with ultrasound-only polycystic ovaries or polycystic ovary syndrome matched with 12 oocyte recipients.
Intervention(S):
Immature oocyte collection without any ovarian stimulation. In vitro maturation of the oocytes. Embryo transfer of the embryos.
Main Outcome Measure(S):
Immature oocyte collection, maturation, fertilization, and cleavage rates. Implantation, pregnancy, and live birth rates.
Result(S):
A mean of 12.8 +/- 5.1 Germinal-vesicle oocytes were aspirated per collection. The in vitro maturation rate was 68.3% +/- 18.4% with a mean of 8.7 +/- 3.6 mature oocytes per collection. The mean fertilization rate was 73.3% +/- 19.4%. Two to five embryos (median four) were transferred. Six recipients conceived, giving a 50% clinical pregnancy rate per cycle. The mean implantation rate per embryo was 18.2%. The live birth rate per cycle started was 30%.
Conclusion(S):
Collecting immature oocytes from unstimulated ovaries for the purpose of oocyte donation is a simple procedure that totally avoids ovarian stimulation. With appropriate selection of women with ultrasound-only polycystic ovaries or women with the polycystic ovary syndrome, the pregnancy rates of the recipients are comparable with those achieved through conventional IVF oocyte donor cycles.
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