Time-lapse enabled assessment

Time-lapse image capture allows dynamic and flexible scoring of the developing embryo, and allows the embryologist to review and analyse the full course of embryo development at their convenience.

 


Observation of exact time of first cleavage

Early Cleavage (EC) has been reported as an important parameter for embryo quality scoring (1-9) however method of fertilization (IVF, ICSI), culture media and stimulation protocols may affect the time at which the first cleavage occurs (11,12,13)).  By dynamic observation of embryo development, external factors which affect division can be assessed and used to correlate the existence of “windows of early cleavage” based on various factors.  In some patients, none of the embryos have cleaved in the EC observation time-point and so assessment must be based on other parameters.  The ability to observe which of the non-EC embryos cleaves first, may then be important for later assessment.

 

Synchrony

It has also been reported that the synchrony in appearance of nuclei after first division (13) and synchrony of subsequent division is also significantly associated with pregnancy success, and can be an indicator of embryo quality (13,14) and that asynchronous divisions, and embryos with odd cell numbers may have similar genetic abnormalities as arrested embryos (15,16).

However asynchrony of division can only be assessed if the embryo has an odd number at the exact time of observation.  We have observed (unpublished results)  that time spent as an “odd” cell can be significantly different between embryos, however some of these proceed to 4-cell by the day 2 observation period.  Time-lapse observation allows assessment of degree of asynchrony.

 

Fragmentation history

Previous time-lapse studies have shown that appearance and disappearance of fragments is a dynamic process and can be very dependant upon observation time point.  During time-lapse analysis, fragments are often reabsorbed and embryos which appear highly fragmented immediately after cleavage, can be very different even half an hour later.  Time-lapse allows the embryologist to observe fragmentation events as well as recovery from fragmentation (13, 17,18).

 

 

 

 

References

  1. Lundin, K., Bergh, C. and Hardarson T. (2001) Human Reprod.  ; Vol.16(12) 2652-2657  Early embryo cleavage is a strong indicator of embryo quality in human IVF

  2. Sakkas D., Shoukir, Y., Chardonnens, D., Bianchi, P.G., Campana A. (1998) Human Reprod.; 13: 182-7 Early cleavage of human embryos to the two-cell stage after intracytoplasmic sperm injection as an indicator of embryo viability

  3. Hesters L. (2008) Fert. Ster. 89:6 Impact of early cleaved zygote morphology on embryo development and in vitro fertilization-embryo transfer outcome: a prospective study.

  4. Bos Mikich, A., Mattos, AL, Ferrari, AN Human Reprod. 2001  16: 2658-61 Early cleavage of human embryos: an effective method for predicting successful IVF/ICSI outcome

  5. Salumets, A., Hyden-Granskog, C., Makinen, S., Suikkari, A.M., Tiitinen, A., Tuuri, T. (2003) Human Reprod. 18: 821-5 Early cleavage predicts the viability of human embryos in elective single embryo transfer procedures

  6. Van Montfoort, A.P., Dumoulin, J.C., Kester, A.D., and Evers J.L. (2004);  Human Reprod. 19:2103-8 Early cleavage is a valuable addition to existing embryo selection parameters: a study using single embryo transfers.

  7. Wharf E., Dimitrakopoulos, A., Khalaf, Y., Pickering, S. (2004)  Reprod Biomed Online 8:212-8 Early embryo development is an indicator of implantation potential.

  8. Windt, M.L., Kruger, T.F., Coetzee, K., Lombard, C.J. (2004) Hum. Reprod; 19:1155 Comparative analysis of pregnancy rates after the transfer of early dividing embryos versus slower dividing embryos.

  9. Fenwick, J., Platteau P., Murdoch, A.P., Herbert, M. (2002) Hum Reprod;17:407-12 Time from insemination to first cleavage predicts developmental competence of human preimplantation embryos in vitro

  10. Fancovits, P., Takacs, F.Z., Tothne, G.Z., Papp, Z., Urbanczek, J.  (2006)  J. Reproductionsmed. Endokrinol. 3(6) 367-372Examination of Early Cleavage and its importance in IVF Treatment.

  11. Yang, W.J., Hwu, Y.M., Lee, R K-K.,  Li, H-S., Fleming, S. (2009) Reprod. Biol. Endocrinol. 7:20: Early-cleavage is a reliable predictor for embryo implantation in the GnRH agonist protocols but not in the GnRH antagonist protocols

  12. Lechniak, (2008) 1: Reprod Biol. Mar;8(1):23-42. Timing of the first zygotic cleavage as a marker of developmental potential of mammalian embryos.

  13. Lemmen, J.G.; Agerholm, I.; Ziebe (2008) Reprod. Biomed Online 17(3):385-391  Kinetic markers of human embryo quality using time-lapse recordings of IVF/ICSI-fertilized oocytes

  14. Scott, L., Finn, A., O’Leary, T., McLellan, S. and J. Hill (2007) Hum. Reprod.  22(1) 230-340 Morphological parameters of early cleavage-stage embryos that correlate with fetal development and delivery: prospective and applied data for increased pregnancy rates.

  15. Hardarson, T., Hanson, C., Sjögren,A., Lundin, K. (2001) Hum. Reprod. 16(2) 313-318 Human embryos with unevenly sized blastomeres have lower pregnancy and implantation rate: indications fo aneuploidy and multinucleation.

  16. Magli, C., Gianaroli, L.Ferraretti, A.P., Lappi, M., Ruberti, A., Farfalli, V. (2007) Fert. Ster. 87(3) 534-540
    Embryo morphology and development are dependent on the chromosomal complement.

  17. Van Blerkorn, J.  (2007) Reprod. Biomed. Online 14(2)191-200: Translocation of the subpasmalemmal cytoplasm in human blastomeres: possible effects on the distribution and inheritance of regulatory domains.

  18. Hardarson, T. (2002) Reprod. Biomed Online 5(1)36-38 Internalization of cellular fragments in a human embryo: time-lapse recordings.