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The endometrial preparation for frozen-thawed euploid blastocyst transfer: a prospective randomized trial comparing clinical results from natural modified cycle and exogenous hormone stimulation with GnRH agonist

  • Assisted Reproduction Technologies
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Abstract

Purpose

The aim of the study was to evaluate two methods of endometrial preparation for frozen-thawed single euploid blastocyst transfer: modified natural and artificial cycle with GnRH-agonist pituitary suppression.

Methods

In this prospective, controlled randomized trial, a total of 236 patients undergoing infertility treatment were randomized in 1:1 ratio; 118 received a frozen-thawed single euploid blastocyst transfer in a modified natural cycle and 118 in an artificial cycle with GnRH-agonist pituitary suppression. In the artificial protocol, GnRH-agonist combined with estradiol valerate was administered. In the natural protocol, only final oocyte maturation was induced using human chorionic gonadotropin administration. The primary end-points were the clinical pregnancy and implantation rates; the secondary end-points were the cost-benefit in terms of drug cost and the number of visits and the woman psychological distress caused by the treatment.

Results

No significant differences were found in clinical pregnancy, implantation, and miscarriage rates between protocols. The number of clinical and ultrasound controls and the number of laboratory dosages and venous samplings were similar in both study groups. No significant differences were found between the groups in the anxiety and depression values before the start of treatment, on the days of progesterone administration, the blastocyst transfer, and pregnancy test.

Conclusions

The findings of this study evidence that in case of frozen-thawed single euploid blastocyst transfer, both protocols are equally effective in terms of clinical outcomes, cost-benefit, and patient compliance. The choice of endometrial preparation protocol should be based on women menstrual and ovulatory characteristics or otherwise on patient need for cycle planning.

Trial registration

www.clinicaltrials.gov with number NCT02378584

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Authors and Affiliations

  1. Centre for Reproductive Medicine, European Hospital, Via Portuense 700, 00149, Rome, Italy

    Ermanno Greco, Katarzyna Litwicka, Cristiana Arrivi, Maria Teresa Varricchio, Alina Caragia, Alessia Greco & Maria Giulia Minasi

  2. GENOMA-Molecular Genetics Laboratory, Via Castel Giubileo, 11, 00138, Rome, Italy

    Francesco Fiorentino

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  1. Ermanno Greco
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  2. Katarzyna Litwicka
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  3. Cristiana Arrivi
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  4. Maria Teresa Varricchio
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  5. Alina Caragia
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  6. Alessia Greco
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  7. Maria Giulia Minasi
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  8. Francesco Fiorentino
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Correspondence to Ermanno Greco.

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The Institutional Review Board of the European Hospital and the Genoma Laboratory approved the study before initiation. All participants gave written consent after having been informed on all aspects of the study. All procedures were performed according to the Helsinki declaration of 1975 and its further modifications.

Additional information

Capsule Frozen-thawed single euploid blastocyst transfer can be successfully performed in a modified-natural cycle and after hormonal endometrial preparation. The protocol choice depends on a women’s ovulatory characteristics or need for cycle planning.

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Greco, E., Litwicka, K., Arrivi, C. et al. The endometrial preparation for frozen-thawed euploid blastocyst transfer: a prospective randomized trial comparing clinical results from natural modified cycle and exogenous hormone stimulation with GnRH agonist. J Assist Reprod Genet 33, 873–884 (2016). https://doi.org/10.1007/s10815-016-0736-y

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