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Study · Randomized controlled trial · n = 66 · 2005

4 results

GnRH antagonist versus long GnRH agonist protocol in poor responders undergoing IVF: a randomized controlled trial.

Cheung LP, Lam PM, Lok IH, Chiu TT, Yeung SY, Tjer CC, Haines CJ

Human reproduction (Oxford, England)17 Dec 2004Cited by 121 (Europe PMC)

Summary

The text of this summary is not shown here, because the article license does not allow reuse. Read it at the source (opens in a new tab)

Text rights: Publisher copyright. Results still quote short attributed sentences.

Results from this study4

4 results from studies that gave the peptide. 4 results from people.

  1. 01HumanRandomized controlled trialEfficacy outcome

    In poor IVF responders, cancellation, stimulation duration, gonadotrophin use and follicle, oocyte and embryo counts did not differ significantly between cetrorelix and buserelin.

    In plain wordsIn poor IVF responders, the listed stimulation outcomes did not differ significantly between cetrorelix and buserelin.

    Peptide
    Cetrorelix
    Outcome
    No significant changeCycle cancellation, stimulation duration, gonadotrophin use and follicle, oocyte and embryo counts
    Study

    n = 66

    Comparator
    Buserelin acetate 600 microg daily
    Outcome group
    Sex hormones and fertility · Reproductive and sexual health
    Studied dose
    0.25 mg dailyAs given in this study (human).

    Source sentences

    Summary
    There were no significant differences in the cycle cancellation rates, duration of stimulation, consumption of gonadotrophins, and mean numbers of mature follicles, oocytes and embryos obtained.
    3 context sentences
    Summary · context
    This is the first published report of a prospective, randomized, controlled trial comparing a fixed, multi-dose GnRH antagonist protocol with a long GnRH agonist protocol in poor responders undergoing IVF.
    Summary · context
    Sixty-six poor responders were randomized into two groups: the study group received 0.25 mg of cetrorelix daily starting on day 6 of stimulation; the control group received 600 microg of buserelin acetate daily starting in the mid-luteal phase of the preceding cycle.
    Summary · context
    Both groups were given a fixed dose of recombinant FSH (300 IU daily) for stimulation.
  2. 02HumanRandomized controlled trialEfficacy outcome

    In poor IVF responders, implantation rates were similar between cetrorelix and buserelin protocols.

    In plain wordsIn poor IVF responders, implantation rates were similar with cetrorelix and buserelin.

    Peptide
    Cetrorelix
    Outcome
    Direction not reportedImplantation rate
    Study

    n = 66

    Comparator
    Buserelin acetate 600 microg daily
    Outcome group
    Sex hormones and fertility · Reproductive and sexual health
    Studied dose
    0.25 mg dailyAs given in this study (human).

    Source sentences

    Summary
    The implantation rates were similar, but the number of embryos transferred was significantly higher for the antagonist group (2.32 +/- 0.58 versus 1.50 +/- 0.83; P = 0.01).
    3 context sentences
    Summary · context
    This is the first published report of a prospective, randomized, controlled trial comparing a fixed, multi-dose GnRH antagonist protocol with a long GnRH agonist protocol in poor responders undergoing IVF.
    Summary · context
    Sixty-six poor responders were randomized into two groups: the study group received 0.25 mg of cetrorelix daily starting on day 6 of stimulation; the control group received 600 microg of buserelin acetate daily starting in the mid-luteal phase of the preceding cycle.
    Summary · context
    Both groups were given a fixed dose of recombinant FSH (300 IU daily) for stimulation.
  3. 03HumanRandomized controlled trialEfficacy outcome

    In poor IVF responders, cetrorelix increased embryos transferred versus buserelin: 2.32 +/- 0.58 versus 1.50 +/- 0.83, P = 0.01.

    In plain wordsIn poor IVF responders, more embryos were transferred with cetrorelix than buserelin.

    Peptide
    Cetrorelix
    Outcome
    IncreaseEmbryos transferred
    Study

    n = 66

    Comparator
    Buserelin acetate 600 microg daily
    Outcome group
    Sex hormones and fertility · Reproductive and sexual health
    Studied dose
    0.25 mg dailyAs given in this study (human).

    Measurements

    Embryos transferred
    2.32 embryos
    cetrorelix
    Unspecified spread
    0.58 embryos
    cetrorelix
    Embryos transferred
    1.5 embryos
    buserelin
    Unspecified spread
    0.83 embryos
    buserelin
    P
    0.01
    between protocols

    Source sentences

    Summary
    The implantation rates were similar, but the number of embryos transferred was significantly higher for the antagonist group (2.32 +/- 0.58 versus 1.50 +/- 0.83; P = 0.01).
    3 context sentences
    Summary · context
    This is the first published report of a prospective, randomized, controlled trial comparing a fixed, multi-dose GnRH antagonist protocol with a long GnRH agonist protocol in poor responders undergoing IVF.
    Summary · context
    Sixty-six poor responders were randomized into two groups: the study group received 0.25 mg of cetrorelix daily starting on day 6 of stimulation; the control group received 600 microg of buserelin acetate daily starting in the mid-luteal phase of the preceding cycle.
    Summary · context
    Both groups were given a fixed dose of recombinant FSH (300 IU daily) for stimulation.
  4. 04HumanRandomized controlled trialEfficacy outcome

    In poor IVF responders, pregnancy rates were numerically higher with cetrorelix than buserelin, without a statistically significant difference.

    In plain wordsIn poor IVF responders, pregnancy rates were higher with cetrorelix than buserelin, but the difference was not statistically significant.

    Peptide
    Cetrorelix
    Outcome
    No significant changePregnancy rate
    Study

    n = 66

    Comparator
    Buserelin acetate 600 microg daily
    Outcome group
    Sex hormones and fertility · Reproductive and sexual health
    Studied dose
    0.25 mg dailyAs given in this study (human).

    Source sentences

    Summary
    The pregnancy rates were also higher in the antagonist group, but the difference was not statistically significant.
    3 context sentences
    Summary · context
    This is the first published report of a prospective, randomized, controlled trial comparing a fixed, multi-dose GnRH antagonist protocol with a long GnRH agonist protocol in poor responders undergoing IVF.
    Summary · context
    Sixty-six poor responders were randomized into two groups: the study group received 0.25 mg of cetrorelix daily starting on day 6 of stimulation; the control group received 600 microg of buserelin acetate daily starting in the mid-luteal phase of the preceding cycle.
    Summary · context
    Both groups were given a fixed dose of recombinant FSH (300 IU daily) for stimulation.

AI wrote and checked these results. AI can make mistakes, so check important results against the source.

Version history

PepBank keeps every version of the data on this study. Status changes from Retraction Watch, Europe PMC and Crossref are listed with their source.

  1. Version 2Current

    28 Oct 2026, 02:03 UTC

    Study results updated

  2. Version 1

    27 Oct 2026, 16:35 UTC

    First added · source update from Europe PMC

Subjects

Terms as the source lists them.

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