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Updated: May 24, 2026
08:51
Human Egg Maturity Assessment and Its Clinical Application
Published on: August 19, 2019
Oocyte maturity in repeated ovarian stimulation.
Jae Eun Lee1, Sang Don Kim, Byung Chul Jee
1Department of Obstetrics and Gynecology, Seoul National University Hospital, Seoul, Korea.
Clinical and Experimental Reproductive Medicine
|March 3, 2012
Summary
Women undergoing repeated in vitro fertilization (IVF) cycles often retrieve immature oocytes consistently. This pattern suggests a patient-specific tendency for oocyte immaturity during ovarian stimulation.
Area of Science:
- Reproductive Endocrinology
- In Vitro Fertilization (IVF)
Background:
- Up to 15% of oocytes retrieved during stimulated IVF cycles are immature.
- Oocyte immaturity can impact IVF success rates.
Purpose of the Study:
- To investigate the trend of oocyte maturity in repeated ovarian stimulation cycles for IVF.
- To determine if oocyte immaturity is a consistent finding in subsequent IVF attempts.
Main Methods:
- 148 patients undergoing two consecutive IVF cycles with identical stimulation protocols were analyzed.
- Ovarian stimulation used FSH, human menopausal gonadotropin, and a flexible GnRH antagonist protocol.
- Oocyte maturity was assessed; immature oocytes (germinal vesicle or metaphase I stage) were cultured for in vitro maturation (IVM).
Main Results:
- Percentages of immature oocytes were similar between the first (30.8%) and second (32.9%) cycles (p=0.466).
- A significant correlation existed between the percentage of immature oocytes in the two cycles (R=0.178, p=0.03).
- Women with consistently high immaturity rates (>40%) showed lower fertilization and pregnancy rates after the second cycle.
Conclusions:
- Immature oocytes tend to be repetitively retrieved in consecutive IVF cycles.
- This suggests a patient-specific factor influencing oocyte maturity during ovarian stimulation.
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