Comparison of outcomes of frozen-thawed transfer of day 5 blastocysts and day 6 blastocysts

Objective: The aim of this study was to evaluate and compare the outcomes of frozenthawed embryo transfer of blastocysts that were expanded at the 5th day of fertilization and blastocysts expanded at the 6th day of fertilization. Material and Methods: Patients who underwent frozen-thawed embryo transfer cycles between 2012 and 2020 in a single infertility center were retrospectively evaluated. A total of 1814 women with frozen embryo transfers of day 5 blastocysts and 227 women with frozen embryo transfers of day 6 blastocysts were included in the study. Outcomes of embryo transfer cycles of day 5 and day 6 blastocysts were compared. Results: Cancellation rate in day 6 blastocyst transfer group was significantly higher than day 5 transfers (5.7% vs. 0.3%; p

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1. Kovacic B, Vlaisavljevic V, Reljic M, Cizek-Sajko M. Developmental capacity of different morphological types of day 5 human morulae and blastocysts. Reprod Biomed Online 2004;8(6):687–94.
2. Park DS, Kim JW, Chang EM, Lee WS, Yoon TK, Lyu SW. Obstetric, neonatal, and clinical outcomes of day 6 vs. day 5 vitrified-warmed blastocyst transfers: Retrospective cohort study with propensity score matching. Front Endocrinol (Lausanne) 2020;11:499.
3. Hashimoto S, Amo A, Hama S, Ito K, Nakaoka Y, Morimoto Y. Growth retardation in human blastocysts increases the incidence of abnormal spindles and decreases implantation potential after vitrification. Hum Reprod 2013;28(6):1528–35.
4. Mirkin S, Nikas G, Hsiu JG, Díaz J, Oehninger S. Gene expression profiles and structural/functional features of the peri-implantation endometrium in natural and gonadotropin-stimulated cycles. J Clin Endocrinol Metab 2004;89(11):5742–52.
5. Shapiro BS, Daneshmand ST, Garner FC, Aguirre M, Ross R. Contrasting patterns in in vitro fertilization pregnancy rates among fresh autologous, fresh oocyte donor, and cryopreserved cycles with the use of day 5 or day 6 blastocysts may reflect differences in embryo-endometrium synchrony. Fertil Steril 2008;89(1):20–6.
6. Barrenetxea G, Delarruzea A, Ganzabal T, Jimenez R, Carbonero K, Mandiola M. Blastocyst culture after repeated failure of cleavage-stage embryo transfers: A comparison of day 5 and day 6 transfers. Fertil Steril 2005;83(1):49–53.
7. Shapiro BS, Richter KS, Harris DC, Daneshmand ST. A comparison of day 5 and day 6 blastocyst transfers. Fertil Steril 2001;75(6):1126–30. 8. Sunkara SK, Siozos A, Bolton VN, Khalaf Y, Braude PR, El-Toukhy T. The influence of delayed blastocyst formation on the outcome of frozenthawed blastocyst transfer: A systematic review and meta-analysis. Hum Reprod 2010;25(8):1906–15.
9. Yang H, Yang Q, Dai S, Li G, Jin H, Yao G, et al. Comparison of differences in development potentials between frozen-thawed D5 and D6 blastocysts and their relationship with pregnancy outcomes. J Assist Reprod Genet 2016;33(7):865–72.
10. Haas J, Meriano J, Laskin C, Bentov Y, Barzilay E, Casper RF, et al. Clinical pregnancy rate following frozen embryo transfer is higher with blastocysts vitrified on day 5 than on day 6. J Assist Reprod Genet 2016;33(12):1553–7.
11. Ferreux L, Bourdon M, Sallem A, Santulli P, Barraud-Lange V, Le Foll N, et al. Live birth rate following frozen–thawed blastocyst transfer is higher with blastocysts expanded on day 5 than on day 6. Hum Reprod 2018;33(3):390–8.
12. Desai N, Ploskonka S, Goodman L, Attaran M, Goldberg JM, Austin C, et al. Delayed blastulation, multinucleation, and expansion grade are independently associated with live-birth rates in frozen blastocyst transfer cycles. Fertil Steril 2016;106(6):1370–8.
13. Taylor TH, Patrick JL, Gitlin SA, Wilson JM, Crain JL, Griffin DK. Comparison of aneuploidy, pregnancy and live birth rates between day 5 and day 6 blastocysts. Reprod Biomed Online 2014;29(3):305–10.
14. Alpha Scientists in Reproductive Medicine and ESHRE Special Interest Group of Embryology. The Istanbul consensus workshop on embryo assessment: Proceedings of an expert meeting. Hum Reprod 2011;26(6):1270–83.
15. Zegers-Hochschild F, Adamson GD, Dyer S, Racowsky C, de Mouzon J, Sokol R, et al. The international glossary on infertility and fertility care, 2017. Fertil Steril 2017;108(3):393–406.
16. Tannus S, Cohen Y, Henderson S, Al Ma’mari N, Shavit T, Son WY, Dahan MH. Fresh transfer of day 5 slow-growing embryos versus deferred transfer of vitrified, fully expanded day 6 blastocysts: Which is the optimal approach? Hum Reprod 2019;34(1):44–51.
17. Kaye L, Will EA, Bartolucci A, Nulsen J, Benadiva C, Engmann L. Pregnancy rates for single embryo transfer (SET) of day 5 and day 6 blastocysts after cryopreservation by vitrification and slow freeze. J Assist Reprod Genet 2017;34(7):913–9.
18. Piccolomini MM, Nicolielo M, Bonetti TC, Motta EL, Serafini PC, Alegretti JR. Does slow embryo development predict a high aneuploidy rate on trophectoderm biopsy? Reprod Biomed Online 2016;33(3):398–403.
19. Levens ED, Whitcomb BW, Hennessy S, James AN, Yauger BJ, Larsen FW. Blastocyst development rate impacts outcome in cryopreserved blastocyst transfer cycles. Fertil Steril 2008;90(6):2138–43.