Related Experiment Video
Updated: Jul 11, 2026
10:36
In Vitro Imaging and Quantification of the Drug Targeting Efficiency of Fluorescently Labeled GnRH Analogues
Published on: March 21, 2017
Are GnRH antagonists comparable to agonists for use in IVF?
J A Huirne1, R Homburg, C B Lambalk
1Division of Reproductive Medicine, Department of Obstetrics and Gynaecology, Vrije Universiteit Medical Centre, 1007 MB, Amsterdam, The Netherlands.
Human Reproduction (Oxford, England)
|September 18, 2007
Summary
Optimal outcomes in IVF may be achieved with early suppression of hormones using gonadotropin-releasing hormone (GnRH) antagonist regimens. Further research is needed to compare optimal GnRH agonist and antagonist protocols for pregnancy rates.
Area of Science:
- Reproductive Endocrinology
- In Vitro Fertilization (IVF)
Background:
- Current meta-analyses comparing GnRH agonists and antagonists often include suboptimal GnRH antagonist regimens.
- A definitive comparison of optimal GnRH agonist and antagonist protocols is lacking.
Purpose of the Study:
- To critically appraise GnRH antagonist regimens for their impact on follicular development and IVF outcomes.
- To determine the optimal timing and method for GnRH antagonist administration.
Main Methods:
- Critical appraisal of existing studies on GnRH antagonist regimens.
- Postulation of optimal follicular development based on early endogenous FSH suppression.
- Analysis of LH and progesterone suppression patterns during stimulation.
Main Results:
- Early suppression of endogenous FSH is postulated to optimize follicular development.
- Stable and early suppression of LH and progesterone may enhance implantation and pregnancy rates.
- Single-dose and flexible GnRH antagonist protocols appear less advantageous.
Conclusions:
- Early GnRH antagonist administration (stimulation day 1) or oral contraceptive pretreatment can achieve early FSH and LH suppression.
- Further high-powered studies are required to compare long GnRH agonist protocols with optimized 'long' GnRH antagonist protocols for pregnancy rates.
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