---
title: Does a premenstrual GnRH antagonist injection reduce variation in egg follicle sizes for fertility treatment?
description: Yes, in 25 women, a single premenstrual GnRH antagonist injection reduced the sizes of early egg follicles and the differences between them. This may help imp
url: https://niyora.com/research/papers/premenstrual-administration-of-gonadotropin-releasing-hormone-antagonist-2004/
---

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- Does a premenstrual GnRH antagonist injection reduce variation in egg follicle sizes for fertility treatment?

Cohort study, 2004

# Does a premenstrual GnRH antagonist injection reduce variation in egg follicle sizes for fertility treatment?

Yes, in 25 women, a single premenstrual GnRH antagonist injection reduced the sizes of early egg follicles and the differences between them. This may help improve fertility treatment, though results are from a single center.

 Moderate study design

25 women undergoing fertility treatment in France

## What they did

This study followed 25 women (50 cycles total) at a French university hospital. On cycle day 2, researchers measured early egg follicles by ultrasound and measured hormones. On day 25 of the cycle, women received a single injection of cetrorelix acetate (3 mg). On the following cycle day 2, measurements were repeated.

## What they found

Follicle diameters were smaller (4.1 +/- 0.9 mm vs. 5.5 +/- 1.0 mm) and follicle-to-follicle size differences decreased with the antagonist. FSH was lower (4.5 +/- 1.9 vs. 6.7 +/- 2.4 mIU/mL), E2 was lower (23 +/- 13 vs. 46 +/- 26 pg/mL), and inhibin B was lower (52 +/- 30 vs. 76 +/- 33 pg/mL) with the antagonist.

## What it means for you

A single injection of a GnRH antagonist given premenstrually may help standardize egg follicle development for fertility treatment. However, this is from a single center and needs confirmation in larger studies.

3 mg

Cetrorelix acetate dose

4.1 mm

Follicle diameter after antagonist

50 cycles

Total cycles studied

## About the study

Original title Premenstrual administration of gonadotropin-releasing hormone antagonist coordinates early antral follicle sizes and sets up the basis for an innovative concept of controlled ovarian hyperstimulation Authors Fanchin R, Castelo Branco A, Kadoch IJ et al. Journal Fertility and sterility Year 2004 Study design Cohort study What was tested Single premenstrual injection of cetrorelix acetate (GnRH antagonist), 3 mg Open access Yes Read the paper [doi.org/10.1016/j.fertnstert.2003.11.037](https://doi.org/10.1016/j.fertnstert.2003.11.037)

## Topics

[GnRH agonists and ovarian suppression](https://niyora.com/research/topics/treatment-gnrh/)

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