Advertisement

Journal of Assisted Reproduction and Genetics

, Volume 24, Issue 10, pp 471–475 | Cite as

Chemical zona pellucida thinning with acidified Tyrode’s solution: comparison between partial and circumferential techniques

  • Kohji YanoEmail author
  • Chieko Yano
  • Toshiko Kubo
  • Ikuko Ôhashi
  • Nagamasa Maeda
  • Takao  Fukaya
Article

Abstract

Purpose

To compare effectiveness of two different chemical zona thinning techniques.

Method

We studied 163 patients who had experienced IVF or ICSI failures in two or more cycles. Patients were assigned to one of three groups: zona intact (n = 72), partial thinning (n = 59), or circumferential thinning (n = 73). Before transfer, the zonae pellucidae of embryos were thinned partially or circumferentially using acidified Tyrode’s solution.

Results

Implantation rates were 8.9% in the intact zona group, 17.6% in the partial thinning group, and 11.9% in the circumferential thinning group: respective clinical pregnancy rates were 16.7% (12/72), 32.2% (19/59), and 27.4% (20/73). Both rates were significantly higher in the partial thinning group than the intact zona group. For circumferential thinning versus zona intact groups, differences fell short of significance.

Conclusions

Following embryo transfer failure, partial thinning would be recommended over circumferential thinning for successful assisted hatching.

Keywords

Assisted hatching Acidified Tyrode’s solution Partial zona thinning Circumferential zona thinning 

References

  1. 1.
    Perona RM, Wasserman PM. Mouse blastocysts hatch in vitro by using a trypsin-like proteinase associated with cells of mural trophectoderm. Dev Biol 1986;114:42–52.PubMedCrossRefGoogle Scholar
  2. 2.
    Sawada H, Yamasaki K, Hoshi M. Trypsin-like protease from mouse embryos: evidence for the presence in culture medium and its enzymatic properties. J Exp Zool 1990;254:83–7.PubMedCrossRefGoogle Scholar
  3. 3.
    De Felici M, Siracusa G. “Spontaneous” hardening of the zona pellucida of mouse oocytes during in vitro culture. Gamete Res 1982;6:107–13.CrossRefGoogle Scholar
  4. 4.
    Cohen J, Elsner C, Kort H, Massey J, Mayer MP, Wiemer K. Impairment of the hatching process following IVF in the human and improvement of implantation by assisted hatching using micromanipulation. Hum Reprod 1990;5:7–13.PubMedGoogle Scholar
  5. 5.
    Cohen J, Alikani M, Trowbridge J, Rosenwaks Z. Implantation enhancement by selective assisted hatching using zona drilling of human embryos with poor prognosis. Hum Reprod 1992;7:685–91.PubMedGoogle Scholar
  6. 6.
    Khalifa EA, Tucker MJ, Hunt P. Cruciate thinning of the zona pellucida for more successful enhancement of blastocyst hatching in the mouse. Hum Reprod 1992;7:532–6.PubMedGoogle Scholar
  7. 7.
    Gordon JW, Dapunt U. Restoration of normal implantation rates in mouse embryos with a hatching impairment by use of a new method of assisted hatching. Fertil Steril 1993;59:1302–7.PubMedGoogle Scholar
  8. 8.
    Tucker MJ, Biol MI, Wiker SR, Kort HI. Embryonal zona pellucida thinning and uterine transfer. Assist Reprod Rev 1993;3:168–71.Google Scholar
  9. 9.
    Schoolcraft WB, Jones GS, Schlenker T. Assisted hatching in the treatment of poor prognosis in vitro fertilization candidates. Fertil Steril 1994;62:551–4.PubMedGoogle Scholar
  10. 10.
    Bider D, Livshits A, Yonish M. Assisted hatching by zona drilling of human embryos in women of advanced age. Hum Reprod 1997;12:317–20.PubMedCrossRefGoogle Scholar
  11. 11.
    Magli MC, Gianaroli L, Ferraretti AP, Fortini D, Aicardi G. Rescue of implantation potential in embryos with poor prognosis by assisted zona hatching. Hum Reprod 1998;13:1331–5.PubMedCrossRefGoogle Scholar
  12. 12.
    Graham MC, Hoeger KM, Phipps WR. Initial IVF-ET experience with assisted hatching performed 3 days after retrieval followed by day 5 embryo transfer. Fertil Steril 2000;74:668–71.PubMedCrossRefGoogle Scholar
  13. 13.
    Fong C-Y, Bongso A, Ng S, Anandakumar C, Trounson A, Ratnam S. On going normal pregnancy after transfer of zona-free blastocysts; implications for embryo transfer in the human. Hum Reprod 1997;3:557–60.CrossRefGoogle Scholar
  14. 14.
    Mansour RT, Rhodes CA, Aboulghar MA, Serour GI, Kamal A. Transfer of zona-free embryos improves outcome in poor prognosis patients: a prospective randomized controlled study. Hum Reprod 2000;15:1061–4.PubMedCrossRefGoogle Scholar
  15. 15.
    Nichols J, Gardner RL. Effect of damage to zona pellucida on development of preimplantation embryos in the mouse. Hum Reprod 1989;4:180–7.PubMedGoogle Scholar
  16. 16.
    Tucker MJ, Luecke N, Wilker S, Wright G. Chemical removal of the outside of the zona pellucida of day 3 human embryos has no impact on implantation rate. J Assist Reprod Genet 1993;10:187–91.PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media, LLC 2007

Authors and Affiliations

  • Kohji Yano
    • 1
    Email author
  • Chieko Yano
    • 1
  • Toshiko Kubo
    • 1
  • Ikuko Ôhashi
    • 1
  • Nagamasa Maeda
    • 2
  • Takao  Fukaya
    • 2
  1. 1.IVF CenterYano Maternity ClinicMatsuyamaJapan
  2. 2.Department of Aging and Reproductive MedicineKochi Medical SchoolKochiJapan

Personalised recommendations