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Updated: Feb 22, 2026

In Vitro Imaging and Quantification of the Drug Targeting Efficiency of Fluorescently Labeled GnRH Analogues
Published on: March 21, 2017
Comparison of long GnRH agonist versus GnRH antagonist protocol in poor responders
Sadık Şahin1, Selçuk Selçuk1, Belgin Devranoğlu1
1Zeynep Kamil Women and Children's Diseases Education and Research Hospital, Clinics of Obstetrics and Gynecology, İstanbul, Turkey.
Objective:
To compare long GnRH agonist with GnRH antagonist protocol in poor responders.
Materials And Methods:
Medical charts of 531 poor responder women undergoing in-vitro fertilization (IVF) cycle at Zeynep Kamil Maternity and Children's Hospital, IVF Center were retrospectively analysed. Those who received at least 300 IU/daily gonadotropin and had ≤3 oocytes retrieved were enrolled in the study. Poor responders were categorized into two groups as those who received long GnRH agonist or GnRH antagonist regimen.
Results:
Treatment duration and total gonadotropin dosage were significantly higher in women undergoing the long GnRH agonist regimen compared with the GnRH antagonist regimen (p<0.001 for both). Although the number of total and mature oocytes retrieved was similar between the groups, good quality embryos were found to be higher in the GnRH antagonist regimen. The day of embryo transfer and number of transferred embryos were similar in the groups. No statistically significant differences were detected in pregnancy (10.5% vs 14.1%), clinical pregnancy (7.7% vs 10.6%) and early pregnancy loss rates (27.2% vs 35%) between the groups.
Conclusion:
GnRH antagonist regimen may be preferable to long GnRH regimen as it could decrease the cost and treatment duration in poor responders.
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