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Updated: Apr 23, 2026

Fertility Preservation Through Oocyte Vitrification: Clinical and Laboratory Perspectives
Published on: September 16, 2021
Prolonged GnRH suppression period in controlled ovarian hyperstimulation cycles: Impacts on IVF outcomes?
Background:
Prolonged GnRH-a administration in IVF cycles may have some advantages related to the treatment outcomes.
Objective:
In this study, we aimed to analyse the effect of prolonged gonadotropin releasing hormone agonist (GnRH-a) administration on controlled ovarian hyperstimulation outcomes of in vitro fertilization (IVF) patients.
Materials And Methods:
In this retrospective study, 55 patients with a GnRH-a administration period more than 10 days were compared with 55 patients whose same period was ≤10 days with respect to the demographic characteristics, metaphase II (MII) oocyte ratio, grade I (GI) embryo ratio, blastocyst ratio, fertilization, implantation, and the clinical pregnancy rates.
Results:
The mean hospital visit count of the prolonged GnRH-a patients was 2.6±0.4. As we expected, total GnRH-a doses used during hypophyseal down regulation were significantly different between the groups (p<0.0001). MII oocyte, G1 embryo and the blastocyst ratios were also significantly different between the groups (p<0.0001; p<0.01 and p<0.05). All the other parameters were insignificant.
Conclusion:
Prolonged GnRH-a administration during ovarian suppression in IVF patients may have positive impacts on the oocytes and the embryos, but this affect may not be observed in the overall pregnancy rates.
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