The association between quality of supernumerary embryos in a cohort and implantation potential of the transferred blastocyst
Despite studies focused on the association between embryo morphology and implantation potential, it is unknown how the collective quality of the supernumerary embryos in a cohort is associated with the implantation rate (IR) of the transferred embryo. This study tested the hypothesis that a relationship exists between the quality of the supernumerary cohort and IR.
A retrospective cohort study of first fresh autologous IVF cycles from 05/2012 to 09/2016, with ≥ 3 blastocysts, resulting in a single blastocyst transfer (n = 819) was performed. Cohorts were grouped in two ways: by mean priority score (PS; 1 being best) of supernumerary embryos and by percent supernumerary embryos with low implantation potential. The relationship between cohort quality and IR was assessed using logistic regression.
As mean cohort PS increased, IR of the transferred embryo decreased (test for linear trend, p = 0.05). When ≥ 75% of the supernumerary cohort was predicted to have low implantation potential, IR of the transferred embryo was significantly lower compared to when < 75% of the cohort was predicted to have low implantation potential (OR 0.71; 95% CI (0.53–0.94)). All associations were attenuated when adjusting for PS of the transferred embryo.
Our findings suggest that quality of supernumerary embryos is associated with IR of the transferred embryo, among patients with ≥ 3 blastocysts available on day 5. As cohort quality declines and the proportion of low implantation potential embryos increases, the IR of the transferred embryo declines. These associations are attenuated when controlling for quality of the transferred embryo, suggesting that the relationship between embryo cohort quality and implantation is not independent of the transferred embryo quality.
KeywordsEmbryo quality Embryo score Embryo morphology Implantation Supernumerary embryo
- 4.Thompson SM, Onwubalili N, Brown K, Jindal SK, PG MG. Blastocyst expansion score and trophectoderm morphology strongly predict successful clinical pregnancy and live birth following elective single embryo blastocyst transfer (eSET): a national study. J Assist Reprod Genet. 2013;30:1577–81. https://doi.org/10.1007/s10815-013-0100-4.CrossRefPubMedPubMedCentralGoogle Scholar
- 9.Heitmann RJ, Hill MJ, Richter KS, DeCherney AH, Widra EA. The simplified SART embryo scoring system is highly correlated to implantation and live birth in single blastocyst transfers. J Assist Reprod Genet. 2013;30:563–7. https://doi.org/10.1007/s10815-013-9932-1.CrossRefPubMedPubMedCentralGoogle Scholar
- 13.Racowsky C, Stern JE, Gibbons WE, Behr B, Pomeroy KO, Biggers JD. National collection of embryo morphology data into Society for Assisted Reproductive Technology Clinic Outcomes Reporting System: associations among day 3 cell number, fragmentation and blastomere asymmetry, and live birth rate. Fertil Steril. 2011;95:1985–9. https://doi.org/10.1016/j.fertnstert.2011.02.009.CrossRefPubMedGoogle Scholar
- 14.Vernon M, Stern JE, Ball GD, Wininger D, Mayer J, Racowsky C. Utility of the national embryo morphology data collection by the Society for Assisted Reproductive Technologies (SART): correlation between day-3 morphology grade and live-birth outcome. Fertil Steril. 2011;95:2761–3. https://doi.org/10.1016/j.fertnstert.2011.02.008.CrossRefPubMedGoogle Scholar
- 19.Hill MJ, Richter KS, Heitmann RJ, Lewis TD, DeCherney AH, Graham JR, et al. Number of supernumerary vitrified blastocysts is positively correlated with implantation and live birth in single-blastocyst embryo transfers. Fertil Steril. 2013;99:1631–6. https://doi.org/10.1016/j.fertnstert.2013.01.130.CrossRefPubMedPubMedCentralGoogle Scholar
- 20.Stern JE, Lieberman ES, Macaluso M, Racowsky C. Is cryopreservation of embryos a legitimate surrogate marker of embryo quality in studies of assisted reproductive technology conducted using national databases? Fertil Steril. 2012;97:890–3. https://doi.org/10.1016/j.fertnstert.2011.12.050.CrossRefPubMedGoogle Scholar
- 25.Armstrong S, Arroll N, Cree LM, Jordan V, Farquhar C. Time-lapse systems for embryo incubation and assessment in assisted reproduction. Cochrane Database Syst Rev. 2015;(2):CD011320. https://doi.org/10.1002/14651858.CD011320.pub2.
- 27.Ginsburg ES, Baker VL, Racowsky C, Wantman E, Goldfarb J, Stern JE. Use of preimplantation genetic diagnosis and preimplantation genetic screening in the United States: a Society for Assisted Reproductive Technology Writing Group paper. Fertil Steril. 2011;96:865–8. https://doi.org/10.1016/j.fertnstert.2011.07.1139.CrossRefPubMedGoogle Scholar
- 28.Chang J, Boulet SL, Jeng G, Flowers L, Kissin DM. Outcomes of in vitro fertilization with preimplantation genetic diagnosis: an analysis of the United States Assisted Reproductive Technology Surveillance Data, 2011-2012. Fertil Steril. 2016;105:394–400. https://doi.org/10.1016/j.fertnstert.2015.10.018.CrossRefPubMedGoogle Scholar
- 29.Paternot G, Wetzels AM, Thonon F, Vansteenbrugge A, Willemen D, Devroe J, et al. Intra- and interobserver analysis in the morphological assessment of early stage embryos during an IVF procedure: a multicentre study. Reprod Biol Endocrinol. 2011;9:127. https://doi.org/10.1186/1477-7827-9-127.CrossRefPubMedPubMedCentralGoogle Scholar