QUALITY OF BLASTOCYST IN VITRO AND MULTIPLE PREGNANCIES
Abstract
Background. The blastocysts, obtained from in vitro fertilization, have different morphologic characteristics. The aim of the study is to investigate the effect of morphology of transferred blastocysts on pregnancy and multiple pregnancy rate.
Methods. The quality of blastocysts was evaluated by four parameters: amount of embryo mass transformed into the blastocyst, blastocoel expansion, shape of inner cell mass and proliferation of trophectoderm cells. In the first group the blastocysts with four optimal parameters were arranged. The second group was formed from blastocysts with one nonoptimal parameter and the third group from blastocysts with more nonoptimal parameters. The results of 175 transfers of two blastocysts from first group, 65 transfers of two blastocysts from second and 20 transfers of two blastocysts from third group were analysed retrospectively.
Results. Implantation rate was the highest in the first group of transfers and differed significantly in comparison to second and third group (54.7% vs. 31.5% vs. 7.5%; p < 0.05). Most pregnancies were achieved after the transfer of two optimal blastocysts in comparison to other groups of transfers (62.3% vs. 40% vs. 15%; p < 0.05). Multiple pregnancy rate was 56.9% in the first group, 23% in the second group, while in the third group of transfers there was no multiple pregnancy.
Conclusions. By selecting the blastocysts for transfer into the uterus it is advantageous that blastocsyt morphology characteristics are taken into the consideration. Using our blastocyst scoring system it is possible to select out the high quality blastocysts. The probability of implantation by them is more than 50%, for that reason only one such blastocyst could be transferred without any effect on pregnancy rate.
Downloads
References
Gardner DK, Schoolcraft WB. In vitro culture of human blastocysts. In: Jansen R, Mortimer D eds. Toward reproductive certainty: fertility and genetics beyond 1999. Carnforth, UK: Parthenon Publishing, 1999: 378– 88.
Gardner DK, Vella P, Lane M, Wagley L, Schlenker T, Schoolcraft WB. Culture and transfer of human blastocysts increases implantation rates and reduces the need for multiple embryo transfers. Fertil Steril 1998; 68: 84– 8.
Diaz-Cueto L, Gerton GL. The influence of growth factors on the development of preimplantation mammalian embryos. Arc Med Res 2001; 32: 619– 26.
Hardy K, Hooper MA, Handyside AH, Rutherford AJ, Winston RM, Leese HJ. Non-invasive measurement of pyruvate and glucose uptake and lactate production by single human preimplantation embryo. Hum Reprod 1989; 4: 188–91.
Gardner DK, Lane M, Stevens J, Schoolcraft WB. Nonivasive assessment of human embryo nutrient consumption as a measure of developmental potential. Fertil Steril 2001; 76: 1175–80.
Houghton FD, Hawkhead JA, Humpherson PG, Hogg JE, Balen AH, Rutherford AJ, Leese HJ. Non-invasive amino acid turnover predicts human embryo developmental capacity. Hum Reprod 2002; 17: 999–1005.
Ackerman SB, Swanson RJ, Stokes GK, Veck LL. Culture of mouse preimplantation embryos as a quality control assay for human in vitro fertilization. Gamete Res 1984; 9: 145–52.
Vlaisavljević V, Kovačič B. Procjena embriotoksičnosti materijala upotrebljavanih u radu IVF laboratorija. Jugosl ginekol perinatol 1991; 3: 45-8.
Shoukir Y, Chardonnens D, Campana A, Bischof P, Sakkas D. The rate of development and time of transfer play different roles in influencing the viability of human blastocysts. Hum Reprod 1998; 13: 676–81.
Balaban B, Urman B, Sertac A, Alatas C, Aksoy S, Mercan R. Blastocyst quality affects the success of blastocyst-stage embryo transfer. Fertil Steril 2000; 74: 282–7.
Yoon HG, Yoon SH, Son WY, Im KS, Lim JH. High implantation and pregnancy rates with transfer of human hatching day 6 blastocysts. Fertil Steril 2001; 75: 832–3.
Richter KS, Harris DC, Daneshmand ST, Shapiro BS. Quantitative grading of a human blastocyst: optimal inner cell mass size and shape. Fertil Steril 2001; 76: 1157–67.
Hartshorne GM, Elder K, Crow J, Dyson H, Edwards RG. The influence of in-vitro development upon post-thaw survival and implantation of cryopreserved human blastocysts. Hum Reprod 1991; 6: 136–41.
Vlaisavljević V, Kovačič B, Reljič M, Gavrić Lovrec V, Čižek-Sajko M. Is there any benefit from the culture of a single oocyte to a blastocyst-stage embryo in unstimulated cycles? Hum Reprod 2001; 16: 2379–83.
Kovačič B, Vlaisavljević V, Reljič M, Gavrić Lovrec V. Clinical outcome of day 2 versus day 5 transfer in cycles with one or two developed embryos. Fertil Steril 2002; 77: 529–36.
The Author transfers to the Publisher (Zdravniški vestnik/Slovenian Medical Journal) all economic copyrights following form Article 22 of the Slovene Copyright and Related Rights Act (ZASP), including the right of reproduction, the right of distribution, the rental right, the right of public performance, the right of public transmission, the right of public communication by means of phonograms and videograms, the right of public presentation, the right of broadcasting, the right of rebroadcasting, the right of secondary broadcasting, the right of communication to the public, the right of transformation, the right of audiovisual adaptation and all other rights of the author according to ZASP.
The aforementioned rights are transferred non-exclusively, for an unlimited number of editions, for the term of the statutory
The Author can make use of his work himself or transfer subjective rights to others only after 3 months from date of first publishing in the journal Zdravniški vestnik/Slovenian Medical Journal.
The Publisher (Zdravniški vestnik/Slovenian Medical Journal) has the right to transfer the rights, acquired parties without explicit consent of the Author.
The Author consents that the Article be published under the Creative Commons BY-NC 4.0 (attribution-non-commercial) or comparable licence.
