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Comparative Study
. 1999 Aug;16(7):358-62.
doi: 10.1023/a:1020589829458.

Comparison of pregnancy outcome of pronuclear- and multicellular-stage frozen-thawed embryo transfers

S Kattera  1 , P Shrivastav, I Craft
Affiliations
Comparative Study

Comparison of pregnancy outcome of pronuclear- and multicellular-stage frozen-thawed embryo transfers

S Kattera et al. J Assist Reprod Genet. 1999 Aug.

Abstract

Purpose: Our purpose was to determine if supernumerary embryos generated by in vitro fertilization (IVF) and intracytoplasmic sperm injection (ICSI) should be frozen (using 1,2-propanediol) at the pronuclear or multicellular stage.

Methods: The study was a retrospective analysis conducted at the Dubai Gynaecology & Fertility Centre of the Department of Health & Medical Services, Dubai, U.A.E. One hundred forty-one women undergoing frozen-thawed embryo replacement cycles with IVF generated embryos and 84 women undergoing the same with ICSI generated embryos.

Results: Supernumerary, IVF-generated embryos frozen at the multicellular stage had a significantly higher rate of survival on thawing (73.9%) than embryos frozen at the pronuclear stage (64.4%). The morphological grades of the embryos in the two groups were similar, but a significantly higher pregnancy rate was obtained with embryos frozen at the multicellular stage (22.8%) than with pronuclear-stage embryos (14.8%). Similarly, with ICSI-generated embryos, significantly higher survival was seen with multicellular-stage frozen embryos (74.8%) than pronuclear-stage embryos (64.4%). The morphological grades of the embryos and pregnancy outcomes of the two groups were similar.

Conclusions: Supernumerary embryos generated by IVF and ICSI should be frozen at the multicellular stage so as to allow selection of the best embryos for transfer and embryo freezing of only robust embryos.

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References

    1. Trounson A, Mohr L. Human pregnancy following cryopreservation, thawing and transfer of eight cell embryo. Nature. 1983;305:707–709. - PubMed
    1. Cohen J, Simons RF, Edwards RG, Fehilly CB, Fishel SB. Pregnancies following the frozen storage of expanding human blastocysts. J Vitro Fert Embryo Transfer. 1985;2:59–64. - PubMed
    1. Mandelbaum J, Junca AM, Plachot M, Alnot MO, Alvarez S, Debache C, et al. Human embryo cyropreservation, extrinsic and intrinsic parameters of success. Hum Reprod. 1987;2:709–715. - PubMed
    1. Testart J, Lassalle B, Forman R, Gazengel A, Belaishch-Allart J, Hazout A, et al. Factors influencing the success rate of human embryo freezing in an in vitro fertilisation and embryo transfer program. Fertil Steril. 1987;48:107–112. - PubMed
    1. Cohen J, Inge KL, Wiker SR, Wright G. Duration of storage of cyropreserved human embryos. J Vitro Fert Embryo Transfer. 1988;5:301–303. - PubMed

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