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CompletedNCT01005784Updated Nov 1, 2009

Fixed Versus Flexible Gonadotropin-releasing Hormone (GnRH) Antagonist Initiation

A Phase 4 interventional study of Cetrorelix (Cetrotide) and Cetrorelix (Cetrotide) in Subfertility, sponsored by Aristotle University Of Thessaloniki. Completed at 1 site in Greece. Open to female participants aged 18 Years to 39 Years. Per ClinicalTrials.gov, last updated 2009-11-01.

Sponsored by Aristotle University Of Thessaloniki · Phase 4, Interventional, and Treatment

Phase
Phase 4
Study type
Interventional
Enrollment
146
Allocation
Randomized
Ages
18 Years to 39 Years
Sex
Female
01

Study summary

This is a comparison of pregnancy achievement between two GnRH antagonist protocols which differ in the timing of GnRH antagonist initiation.

02

Conditions studied

  • Subfertility

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Keywords

  • GnRH antagonists
03

In context

Infertility

2,506 studies on the registry are indexed under Infertility; 407 are open to participants now.

This study's enrollment of 146 is above the median of 120 across 1,698 interventional studies indexed under Infertility.

Browse Infertility studies →

Lead sponsor

Aristotle University Of Thessaloniki is the lead sponsor of 274 studies on the registry; 56 are open to participants now.

Counted across the registry records on this site, refreshed daily.

04

Who can participate

Ages eligible
18 Years to 39 Years
Sexes eligible
Female
Accepts healthy volunteers
No

Inclusion criteria

  • \< 39 years of age
  • BMI 18.5-29.9
  • \<= 3 previous IVF cycles

Exclusion criteria

Exclusion Criteria:

  • PCOS
  • Endometriosis
05

Study design

Phase
Phase 4
Primary purpose
Treatment
Allocation
Randomized
Intervention model
Parallel assignment
Masking
None (open label)
Enrollment
146 participants (actual)

Study arms

  • Active comparator
    fixed

    Drug: Cetrorelix (Cetrotide)

  • Experimental
    flexible

    Drug: Cetrorelix (Cetrotide)

Interventions

  • DrugCetrorelix (Cetrotide)

    flexible antagonist administration according to specified criteria

    Also known as: Cetrorelix, Cetrotide, Serono

  • DrugCetrorelix (Cetrotide)

    fixed antagonist administration on day 6 of ovarian stimulation

    Also known as: Cetrorelix, Cetrotide, Serono

06

What researchers measure

Primary outcomes

  1. Luteinizing hormone rise

    Time frame: 3-14 days (duration of ovarian stimulation)

07

Study locations

1 site
  • Unit for Human Reproduction
    Thessaloniki, Greece
08

References and documents

Publications

  • Kolibianakis EM, Venetis CA, Kalogeropoulou L, Papanikolaou E, Tarlatzis BC. Fixed versus flexible gonadotropin-releasing hormone antagonist administration in in vitro fertilization: a randomized controlled trial. Fertil Steril. 2011 Feb;95(2):558-62. doi: 10.1016/j.fertnstert.2010.05.052. Epub 2010 Jul 16. PubMed 20637457 ↗
09

Updates

Tracking since Sep 25, 2026
No changes since tracking began. The registry record was last updated on Nov 1, 2009, before this site started recording changes on Sep 25, 2026. Its history is on ClinicalTrials.gov ↗
10

Registry details

Key details

Study ID
NCT01005784
Lead sponsor
Aristotle University Of Thessaloniki
First posted
Nov 1, 2009
Start date
Jun 2005
Primary completion
Jan 2008
Completion
Mar 2008
Last update
Nov 1, 2009

Study contacts

Efstratios Kolibianakis
principal investigator · Unit for Human Reproduction

Oversight

Data monitoring committee
No
View the source record on ClinicalTrials.gov ↗

Not currently enrolling

This study is completed, as verified in Oct 2009. You cannot join it, but the record below documents what was studied.

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