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Updated: Feb 18, 2026

Human Egg Maturity Assessment and Its Clinical Application
Published on: August 19, 2019
The effect of 24 hours delay in oocyte maturation triggering in IVF/ICSI cycles with antagonist protocol and
Robab Davar1, Elham Naghshineh1,2, Nosrat Neghab1
1Research and Clinical Center for Infertility, Yazd Reproductive Sciences Institute, Shahid Sadoughi University of Medical Sciences, Yazd, Iran.
Background:
The best time of final oocyte maturation triggering in assisted reproduction technology protocols is unknown. This time always estimated by combined follicular size and blood progesterone level.
Objective:
The aim of this study was evaluation of the effect of delaying oocyte maturation triggering by 24 hr on the number of mature oocytes (MII) and other in vitro fertilization cycle characteristics in antagonist protocols with not-elevated progesterone (p ≤1 ng/ml).
Materials And Methods:
All patients' candidate for assisted reproduction technology underwent controlled ovarian hyperstimulation by antagonist protocol. When at least 3 follicles with ≥18 mm diameters were seen by vaginal ultrasonography; blood progesterone level was measured. The patients who had progesterone level ≤1 ng/dl entered the study. The participants' randomizations were done and patients were divided into two groups. In the first group, final oocyte maturation was done by human chorionic gonadotropin at the same day, but in the second group, this was performed 24 hr later. Oocytes retrieval was done 36 hr after human chorionic gonadotropin trigger by transvaginal ultrasound guide.
Results:
Number of retrieved oocytes, mature oocytes (MII), fertilized oocytes (2PN), embryos formation, number of transferred embryos and embryos quality has not significant differences between two groups. Also, fertilization and implantation rate, chemical and clinical pregnancy did not differ between groups.
Conclusion:
Delaying of triggering oocyte maturation by 24 hr in antagonist protocol with not-elevated progesterone (progesterone ≤1 ng/ml) have not beneficial nor harmful effect on the number of mature oocytes (MII) and other in vitro fertilization cycle characteristics.
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