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Updated: May 27, 2026
08:51
Human Egg Maturity Assessment and Its Clinical Application
Published on: August 19, 2019
Does empty zona pellucida indicate poor ovarian response on intra cytoplasmic sperm injection cycles?
Ozgur Cinar1, Berfu Demir, Serdar Dilbaz
1Etlik Zubeyde Hanim Women's Health Teaching and Research Hospital, Center for Assisted Reproduction, Etlik, Ankara, Turkey. ozgur.cinar@yahoo.com
Summary
Empty zona pellucida (EZP) formation, a sign of oocyte degeneration, is linked to poorer in vitro fertilization (IVF) outcomes. Higher EZP index indicates reduced oocyte quality and poor ovarian response, impacting IVF success rates.
Area of Science:
- Reproductive Medicine
- In Vitro Fertilization
- Oocyte Biology
Background:
- Empty zona pellucida (EZP) is observed during in vitro fertilization (IVF) procedures.
- The clinical significance and contributing factors of EZP formation require further investigation.
Purpose of the Study:
- To analyze the factors associated with empty zona pellucida (EZP) formation.
- To investigate the relationship between EZP formation and in vitro fertilization (IVF) outcomes.
Main Methods:
- A study involving 104 patients undergoing IVF treatment.
- Calculation of the EZP index (EZPI) based on the ratio of EZP to cumulus-oocyte complexes (COCs).
- Statistical analysis comparing groups with low (EZPI ≤ 0.17) and high (EZPI > 0.17) EZP indices.
Main Results:
- Patients with higher EZPI (Group 2) showed significantly higher age, basal hormone levels, and gonadotropin doses.
- Group 2 had a significantly lower total antral follicle count.
- Oocyte quality, fertilization rates, and embryo quality were significantly lower in Group 2.
Conclusions:
- An elevated EZP index is associated with decreased oocyte quality.
- EZP formation is linked to poor ovarian response in IVF.
- Factors such as gonadotropin-releasing hormone antagonist protocol, follicle size, estradiol levels, fertilization rate, and day-2 embryo score significantly influence EZPI.
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