Embryo Culture and Selection: Morphological Criteria

  • Aparna Hegde
  • Barry BehrEmail author
Part of the Methods in Molecular Biology book series (MIMB, volume 1154)


In this chapter, we have outlined the various morphological criteria for selection of the best embryo at each important milestone encountered in the progress from the oocyte to the blastocyst. As Gerris et al. stated, a combination of one, two, or even three selection points should lead to a more accurate selection of the best embryo, as no one criterion is better than the other. An embryo that fails to meet the entire set of selection criteria must be avoided as culture cannot correct an impaired embryo.

Key words

Embryo grading Oocyte quality Pronuclear morphology Early cleavage Day 2 scoring Day 3 scoring Day 5/6 scoring Cumulative scoring 


  1. 1.
    Van Royen E et al (1999) Characterization of a top quality embryo, a step towards single-embryo transfer. Hum Reprod 14:2345–2349PubMedCrossRefGoogle Scholar
  2. 2.
    Mendoza C et al (2002) Follicular fluid markers of oocyte developmental potential. Hum Reprod 17:1017–1022PubMedCrossRefGoogle Scholar
  3. 3.
    Gardner D et al (2003) Assessment of embryo viability: the ability to select a single embryo for transfer – a review. Placenta 24:S5–S12PubMedCrossRefGoogle Scholar
  4. 4.
    Ebner T et al (2003) Selection based on morphological assessment of oocytes and embryos at different stages of preimplantation development: a review. Hum Reprod 9:251–262CrossRefGoogle Scholar
  5. 5.
    Cummins J et al (1986) A formula for scoring human embryo growth rates in vitro fertilization: its value in predicting pregnancy and in comparison with visual estimates of embryo quality. J In Vitro Fert Embryo Transf 3(5):284–295PubMedCrossRefGoogle Scholar
  6. 6.
    Sakkas D et al (2005) Noninvasive methods to assess embryo quality. Curr Opin Obstet Gynecol 17:283–288PubMedCrossRefGoogle Scholar
  7. 7.
    Johnson M et al (2000) Egg timers: how is developmental time measured in the early vertebrate embryo? BioEssays 22:57–63PubMedCrossRefGoogle Scholar
  8. 8.
    Behr B et al (2011) Cumulative morphological assessment of embryo quality. In: Agarwal A, Varghese A, Peter Nagy Z (eds) Practical manual of in vitro fertilization: advanced methods and novel devices. Humana, New York, NYGoogle Scholar
  9. 9.
    Vlaisavljevic V et al (2001) Is there any benefit from the culture of a single oocyte to a blastocyst-stage embryo in unstimulated cycles. Hum Reprod 16:3279–2383Google Scholar
  10. 10.
    Scott L (2003) The biological basis of non-invasive strategies for selection of human oocytes and embryos. Hum Reprod 9(3):237–249CrossRefGoogle Scholar
  11. 11.
    Wang Q et al (2007) Evaluation of oocyte quality: morphological, cellular and molecular predictors. Reprod Fertil Dev 2007(19):1–12CrossRefGoogle Scholar
  12. 12.
    Sirard M et al (2006) Contribution of the oocyte to embryo quality. Theriogenology 65:126–136PubMedCrossRefGoogle Scholar
  13. 13.
    Sirard M et al (1989) Timing of nuclear progression and protein synthesis necessary for meiotic maturation of bovine oocytes. Biol Reprod 40:1257–1263PubMedCrossRefGoogle Scholar
  14. 14.
    Kastrop P et al (1991) Protein synthesis and phosphorylation patterns of bovine oocytes maturing in vivo. Mol Reprod Dev 29:271–275PubMedCrossRefGoogle Scholar
  15. 15.
    Hunter A et al (1987) Stage-dependent effects of inhibiting ribonucleic acids and protein synthesis on meiotic maturation of bovine oocytes In vitro. J Dairy Sci 70:1646–1651PubMedCrossRefGoogle Scholar
  16. 16.
    Barnes F et al (1991) Embryonic transcription in in vitro cultured bovine embryos. Mol Reprod Dev 29:117–123PubMedCrossRefGoogle Scholar
  17. 17.
    De Sousa P et al (1998) Temporal patterns of embryonic gene expression and their dependence on oogenetic factors. Theriogenology 49:115–128PubMedCrossRefGoogle Scholar
  18. 18.
    Sun Q et al (2001) Translocation of active mitochondria during pig oocyte maturation, fertilization and early embryo development in vitro. Reproduction 122:155–163PubMedCrossRefGoogle Scholar
  19. 19.
    Coticchio G et al (2004) What criteria for the definition of oocyte quality? Ann N Y Acad Sci 1034:132–144PubMedCrossRefGoogle Scholar
  20. 20.
    Combelles C et al (2005) Assessment and optimization of oocyte quality during assisted reproductive technology treatment. Semin Reprod Med 23:277–284PubMedCrossRefGoogle Scholar
  21. 21.
    Hassan-Ali H et al (1998) Perivitelline space granularity: a sign of human menopausal gonadotrophin overdose in intracytoplasmic sperm injection. Hum Reprod 13:3425–3430PubMedCrossRefGoogle Scholar
  22. 22.
    Loutradis D et al (1999) Oocyte morphology correlates with embryo quality and pregnancy rate after intracytoplasmic sperm injection. Fertil Steril 72:240–244PubMedCrossRefGoogle Scholar
  23. 23.
    Kahraman S et al (2000) Relationship between granular cytoplasm of oocytes and pregnancy outcome following intracytoplasmic sperm injection. Hum Reprod 15:2390–2393PubMedCrossRefGoogle Scholar
  24. 24.
    Eichenlaub-Ritter U et al (1995) Recurrent failure in polar body formation and premature chromosome condensation in oocytes from a human patient: indicators of asynchrony in nuclear and cytoplasmic maturation. Hum Reprod 9:2343–2349CrossRefGoogle Scholar
  25. 25.
    Ebner T et al (2000) Prognostic value of first polar body morphology on fertilization rate and embryo quality in intracytoplasmic sperm injection. Hum Reprod 15:427–430PubMedCrossRefGoogle Scholar
  26. 26.
    Chui D et al (1997) Follicular vascularity – the predictive value of transvaginal power Doppler ultrasonography in an in-vitro fertilization programme: a preliminary study. Hum Reprod 12:191–196PubMedCrossRefGoogle Scholar
  27. 27.
    Van Blerkom J et al (1997) The developmental potential of the human oocyte is related to the dissolved oxygen content of follicular fluid: association with vascular endothelial growth factor levels and perifollicular blood flow characteristics. Hum Reprod 12:1047–1055PubMedCrossRefGoogle Scholar
  28. 28.
    Edwards R et al (2000) The role of embryonic polarities in preimplantation growth and implantation of mammalian embryos. Hum Reprod 15(Suppl 6):1–8CrossRefGoogle Scholar
  29. 29.
    Veeck L (1990) The morphological assessment of human oocytes and early concepti. In: Keel BA, Webster BW (eds) Handbook of the laboratory diagnosis and treatment of infertility. CRC, Boca Raton, pp 353–369Google Scholar
  30. 30.
    Laufer N et al (1984) Asynchrony between human cumulus-corona cell complex and oocyte maturation after human menopausal gonadotropin treatment for in vitro fertilization. Fertil Steril 42:366–372PubMedGoogle Scholar
  31. 31.
    Blondin P et al (1995) Oocyte and follicular morphology as determining characteristics for developmental competence in bovine oocytes. Mol Reprod Dev 41(1):54–62PubMedCrossRefGoogle Scholar
  32. 32.
    Warriach HM et al (2004) Thickness of cumulus cell layer is a significant factor in meiotic competence of buffalo oocytes. J Vet Sci 5(3):247–251PubMedGoogle Scholar
  33. 33.
    Nagano M et al (2006) ATP content and maturational/developmental ability of bovine oocytes with various cytoplasmic morphologies. Zygote 14(4):299–304PubMedCrossRefGoogle Scholar
  34. 34.
    Serhal P et al (1997) Oocyte morphology predicts outcome of intracytoplasmic sperm injection. Hum Reprod 12:1267–1270PubMedCrossRefGoogle Scholar
  35. 35.
    Balaban B et al (1998) Oocyte morphology does not affect fertilization rate, embryo quality and implantation rate after intracytoplasmic sperm injection. Hum Reprod 13(12):3431–3433PubMedCrossRefGoogle Scholar
  36. 36.
    Ciotti P et al (2004) First polar body morphology before ICSI is not related to embryo quality or pregnancy rate. Hum Reprod 19(10):2334–2339PubMedCrossRefGoogle Scholar
  37. 37.
    Gabrielsen A et al (2001) The impact of the zona pellucida thickness variation of human embryos on pregnancy outcome in relation to suboptimal embryo development. A prospective randomized controlled study. Hum Reprod 16(10):2166–2170PubMedCrossRefGoogle Scholar
  38. 38.
    De Sutter P et al (1996) Oocyte morphology does not correlate with fertilization rate and embryo quality after intracytoplasmic sperm injection. Hum Reprod 11:595–597PubMedCrossRefGoogle Scholar
  39. 39.
    Wang W et al (2001) Developmental ability of human oocytes with or without birefringent spindles imaged by Polscope before insemination. Hum Reprod 16:1464–1468PubMedCrossRefGoogle Scholar
  40. 40.
    Moon J et al (2003) Visualization of the metaphase II meiotic spindle in living human oocytes using the Polscope enables the prediction of embryonic developmental competence after ICSI. Hum Reprod 18:817–820PubMedCrossRefGoogle Scholar
  41. 41.
    Rienzi L (2005) Significance of morphological attributes of the early embryo. Reprod Biomed Online 10:669–681PubMedCrossRefGoogle Scholar
  42. 42.
    De Vos A et al (1999) Invitro matured metaphase-I oocytes have a lower fertilization rate but similar embryo quality as mature metaphase-II oocytes after intracytoplasmic sperm injection. Hum Reprod 14:1859–1863PubMedCrossRefGoogle Scholar
  43. 43.
    Balakier H et al (2002) Morphological and cytogenetic analysis of human giant oocytes and giant embryos. Hum Reprod 17:2394–2401PubMedCrossRefGoogle Scholar
  44. 44.
    Rosenbusch B et al (2002) Cytogenetic analysis of giant oocytes and zygotes to assess their relevance for the development of digynic triploidy. Hum Reprod 17:2388–2393PubMedCrossRefGoogle Scholar
  45. 45.
    Xia P (1997) Intracytoplasmic sperm injection: correlation of oocyte grade based on polar body, perivitelline space and cytoplasmic inclusions with fertilization rate and embryo quality. Hum Reprod 12:1750–1755PubMedCrossRefGoogle Scholar
  46. 46.
    Hammah S (2005) Oocyte and embryo quality: is their morphology a good criterion? J Gynecol Obstet Biol Reprod 34(7):5S38–5S41Google Scholar
  47. 47.
    Plachot M et al (1988) Chromosome analysis of ovocytes and human embryos collected after fertilization in vitro. A model of natural selection against aneuploidy. Rev Fr Gynecol Obstet 83(10):613–617PubMedGoogle Scholar
  48. 48.
    Van Blerkom J et al (1992) Oocyte dysmorphism and aneuploidy in meiotically – mature human oocytes after ovarian stimulation. Hum Reprod 7:379–390PubMedGoogle Scholar
  49. 49.
    Alikani M et al (1995) Intracytoplasmic sperm injection in dysmorphic human oocytes. Zygote 3:283–288PubMedCrossRefGoogle Scholar
  50. 50.
    Mikkelson A et al (2001) Morphology of in-vitro matured oocytes: impact on fertility potential and embryo quality. Hum Reprod 16:1714–1718CrossRefGoogle Scholar
  51. 51.
    Ebner T et al (1999) Elective embryo transfer selected on the basis of first polar body morphology is associated with increased rates of implantation and pregnancy. Fertil Steril 72:599–603PubMedCrossRefGoogle Scholar
  52. 52.
    Navarro P et al (2009) Relationship between first polar body morphology before intracytoplasmic sperm injection and fertilization rate, cleavage rate, and embryo quality. Int J Gynaecol Obstet 104(3):226–229PubMedCrossRefGoogle Scholar
  53. 53.
    Lasiene K et al (2009) Morphological criteria of assessment of oocyte quality. Medicina (Kaunas) 45(7):505–515Google Scholar
  54. 54.
    Bertrand E et al (1995) Does zona pellucida thickness influence the fertilization rate? Hum Reprod 10(5):1189–1193PubMedGoogle Scholar
  55. 55.
    Shen Y et al (2006) Light retardance by human oocyte spindle is positively related to pronuclear score after ICSI. Reprod Biomed Online 12(6):737–751PubMedCrossRefGoogle Scholar
  56. 56.
    Fang C et al (2007) Visualization of meiotic spindle and subsequent embryonic development in in vitro and in vivo matured human oocytes. J Assist Reprod Genet 24(11):495–499CrossRefGoogle Scholar
  57. 57.
    Battaglia D et al (1996) Influence of maternal age on meiotic spindle in oocytes from naturally cycling women. Hum Reprod 11:2217–2222PubMedCrossRefGoogle Scholar
  58. 58.
    Rienze L et al (2008) Significance of metaphase II human oocyte morphology on ICSI outcome. Fertil Steril 90(5):1692–1700CrossRefGoogle Scholar
  59. 59.
    James A (2007) Human pronuclei as a mode of predicting viability. In: Elder K, Cohen J (eds) Human preimplantation embryo selection. Informa UK Ltd, London, pp 31–40CrossRefGoogle Scholar
  60. 60.
    Van Blerkom J (1990) Occurrence and developmental consequences of abberant cellular organization in meiotically mature oocytes after exogeneous ovarian hyperstimulation. J Electron Microsc Tech 16:324–346PubMedCrossRefGoogle Scholar
  61. 61.
    Tesarik J et al (1999) The probability of abnormal preimplantation development can be predicted by a single static observation on pronuclear stage morphology. Hum Reprod 14:1318–1323PubMedCrossRefGoogle Scholar
  62. 62.
    Scott L et al (2000) The morphology of human pronuclear embryos is positively related to blastocyst development and implantation. Hum Reprod 15:2394–2403PubMedCrossRefGoogle Scholar
  63. 63.
    Payne D et al (1997) Preliminary observations on polar body extrusion and pronuclear formation in human oocytes using time-lapse video cinematography. Hum Reprod 12:532–541PubMedCrossRefGoogle Scholar
  64. 64.
    Manor D et al (1996) Undocumented embryos: do not trash them, FISH them. Hum Reprod 11:2502–2506PubMedCrossRefGoogle Scholar
  65. 65.
    Munne A et al (1998) Chromosome abnormalities in human embryos. Hum Reprod Update 4:842–855PubMedCrossRefGoogle Scholar
  66. 66.
    Sadowy S et al (1998) Impaired development of zygotes with uneven pronuclear size. Zygote 63:137–141CrossRefGoogle Scholar
  67. 67.
    Wright G et al (1990) Observations on the morphology of pronuclei and nucleoli in human zygotes and implications for cryopreservation. Hum Reprod 5:109–115PubMedGoogle Scholar
  68. 68.
    Schatten G (1994) The centrosome and its mode of inheritance: the reduction of the centrosome during gametogenesis and its restoration during fertilization. Dev Biol 165:299–335PubMedCrossRefGoogle Scholar
  69. 69.
    Asch R et al (1995) The stages at which human fertilization arrests microtubule and chromosomal configurations in inseminated oocytes which failed to complete fertilization and development in humans. Hum Reprod 10:1897–1906PubMedGoogle Scholar
  70. 70.
    Edwards R et al (1997) Oocyte polarity and cell determination in early mammalian embryos. Mol Hum Reprod 3:863–905PubMedCrossRefGoogle Scholar
  71. 71.
    Garello C et al (1999) Pronuclear orientation, polar body placement, and embryo quality after intracytoplasmic sperm injection and in-vitro fertilization: further evidence for polarity in human oocytes? Hum Reprod 14:2588–2595PubMedCrossRefGoogle Scholar
  72. 72.
    Tesarik J et al (1989) Development of human male pronucleus: ultrastructure and timing. Gamete Res 24:135–149PubMedCrossRefGoogle Scholar
  73. 73.
    Scott L et al (1998) The successful use of pronuclear embryo transfers the day following oocyte retrieval. Hum Reprod 13:1003–1013PubMedCrossRefGoogle Scholar
  74. 74.
    Scott L (2003) Pronuclear scoring as a predictor of embryo development. Reprod Biomed Online 6:57–60CrossRefGoogle Scholar
  75. 75.
    Scott L et al (2007) Morphological parameters of early cleavage – stage embryos that correlate with fetal development and delivery: prospective and applied data for increased pregnancy rates. Hum Reprod 22(1):230–240PubMedCrossRefGoogle Scholar
  76. 76.
    Montag M et al (2001) Evaluation of pronuclear morphology as the only selection criterion for further embryo culture and transfer: results of a prospective multicentre study. Hum Reprod 16:2384–2389PubMedGoogle Scholar
  77. 77.
    Ludwig M et al (2000) Clinical use of a pronuclear stage score following intracytoplasmic sperm injection: impact on pregnancy rates under the conditions of the German embryo protection law. Hum Reprod 15:325–329PubMedCrossRefGoogle Scholar
  78. 78.
    Zollner U et al (2002) The use of a detailed zygote score after IVF/ICSI to obtain good quality blastocysts: the German experience. Hum Reprod 17:1327–1333PubMedCrossRefGoogle Scholar
  79. 79.
    Senn A et al (2006) Morphological scoring of human pronuclear zygotes for prediction of pregnancy outcome. Hum Reprod 21:234–239CrossRefPubMedGoogle Scholar
  80. 80.
    Kaharman S et al (2002) Pronuclear morphology scoring and chromosomal status of embryos in severe male infertility. Hum Reprod 17:3193–3200CrossRefGoogle Scholar
  81. 81.
    Gianaroli L et al (2003) Pronuclear morphology scoring and chromosomal status of embryos in severe male infertility. Fertil Steril 80:341–349PubMedCrossRefGoogle Scholar
  82. 82.
    Bavister B et al (2000) Mitochondrial distribution and function in oocytes and early embryos. Hum Reprod 15:189–198PubMedCrossRefGoogle Scholar
  83. 83.
    Ceyhan S et al (2009) Biennial review of infertility. Humana, New York, pp 143–184CrossRefGoogle Scholar
  84. 84.
    Salumets A et al (2001) The predictive value of pronuclear morphology of zygotes in the assessment of human embryo quality. Hum Reprod 16:2177–2181PubMedCrossRefGoogle Scholar
  85. 85.
    Nagy Z et al (1998) Timing of oocyte activation, pronucleus formation, and cleavage in humans after intracytoplasmic sperm injection (ICSI) with testicular spermatozoa and after ICSI or invitro fertilization on sibling oocytes with ejaculated spermatozoa. Hum Reprod 13:1606–1612PubMedCrossRefGoogle Scholar
  86. 86.
    Balaban B et al (2001) The effects of pronuclear morphology on embryo quality parameters and blastocyst transfer outcome. Hum Reprod 16:2357–2361PubMedCrossRefGoogle Scholar
  87. 87.
    Ludwig M et al (2000) Experience with the elective transfer of two embryos under the conditions of the German embryo protection law: results of a retrospective data analysis of 2573 transfer cycles. Hum Reprod 15:319–324PubMedCrossRefGoogle Scholar
  88. 88.
    Tesarik J et al (2000) Embryos with high implantation potential after intracytoplasmic sperm injection can be recognized by a simple, non-invasive examination of pronuclear morphology. Hum Reprod 15:1396–1399PubMedCrossRefGoogle Scholar
  89. 89.
    Tesarik J et al (2002) Paternal effects acting during the first cell cycle of human preimplantation development after ICSI. Hum Reprod 17:184–187PubMedCrossRefGoogle Scholar
  90. 90.
    Wittemer C et al (2000) Zygote evaluation: an efficient tool for embryo selection. Hum Reprod 15:2591–2597PubMedCrossRefGoogle Scholar
  91. 91.
    Scott L (2002) Embryologic strategies for overcoming recurrent ART treatment failure. Hum Fertil 5:206–214CrossRefGoogle Scholar
  92. 92.
    Balaban B et al (2004) Pronuclear morphology predicts embryo development and chromosome constitution. Reprod Biomed Online 8(6):695–700PubMedCrossRefGoogle Scholar
  93. 93.
    Gamiz P et al (2003) The effect of pronuclear morphology on early development and chromosomal abnormalities in cleavage-stage embryos. Hum Reprod 18:2413–2419PubMedCrossRefGoogle Scholar
  94. 94.
    Chen C et al (2003) The relationship of pronuclear state morphology and chromosome status at cleavage stage. J Assist Reprod Genet 20(10):413–420PubMedCentralPubMedCrossRefGoogle Scholar
  95. 95.
    Edirisinghe W et al (2005) Association of pronuclear Z score with rates of aneuploidy in in vitro-fertilised embryos. Reprod Fertil Dev 17(5):529–534PubMedCrossRefGoogle Scholar
  96. 96.
    Bavister B (1995) Culture of preimplantation embryos: facts and artifacts. Hum Reprod Update 1:91PubMedCrossRefGoogle Scholar
  97. 97.
    Sakkas D et al (1998) Early cleavage of human embryos to the two-cell stage after intracytoplasmic sperm injection as an indicator of embryo viability. Hum Reprod 13:182–187PubMedCrossRefGoogle Scholar
  98. 98.
    Shoukir Y et al (1997) Early cleavage of in-vitro fertilized human embryos to the 2-cell stage: a novel indicator of embryo quality and viability. Hum Reprod 12:153–156CrossRefGoogle Scholar
  99. 99.
    Van Montfoort A et al (2004) Early cleavage is a valuable addition to existing embryo selection parameters: a study using single embryo transfers. Hum Reprod 19:2103–2108PubMedCrossRefGoogle Scholar
  100. 100.
    Fenwick J et al (2002) Time from insemination to first cleavage predicts developmental competence of human preimplantation embryos in vitro. Hum Reprod 17:407–412PubMedCrossRefGoogle Scholar
  101. 101.
    Edwards R et al (1980) Establishing full term human pregnancies using cleaving embryos grown in vitro. Br J Obstet Gynecol 87:737–757CrossRefGoogle Scholar
  102. 102.
    Bos-Mikish A et al (2001) Early cleavage of human embryos: an effective method for predicting successful IVF/ICSI outcome. Hum Reprod 16:2658–2661CrossRefGoogle Scholar
  103. 103.
    Lundin K et al (2001) Early embryo cleavage is a strong indicator of embryo quality in human IVF. Hum Reprod 16:2652–2657PubMedCrossRefGoogle Scholar
  104. 104.
    Petersen C et al (2001) Embryo selection by the first cleavage parameter between 25 and 27 h after ICSI. J Assist Reprod Genet 18:209–212CrossRefPubMedGoogle Scholar
  105. 105.
    Sakkas D et al (2001) Assessment of early cleaving in vitro fertilized human embryos at the 2- cell stage before transfer improves embryo selection. Fertil Steril 76:1150–1156PubMedCrossRefGoogle Scholar
  106. 106.
    Giorgetti C et al (2007) Early cleavage: an additional predictor of high implantation rate following elective single embryo transfer. Reprod Biomed Online 14(1):85–91PubMedCrossRefGoogle Scholar
  107. 107.
    Hardarson T et al (2001) Human embryos with unevenly sized blastomeres have lower pregnancy and implantation rates: indications for aneuploidy and multinucleation. Hum Reprod 16:313–318PubMedCrossRefGoogle Scholar
  108. 108.
    Terriou P et al (2007) Relationship between even early cleavage and day 2 embryo score and assessment of their predictive value for pregnancy. Reprod Biomed Online 14(3):294–299PubMedCrossRefGoogle Scholar
  109. 109.
    Guerif F (2007) Limited value of morphological assessment at days 1 and 2 to predict blastocyst developmental potential: a prospective study based on 4042 embryos. Hum Reprod 22:1973–1981PubMedCrossRefGoogle Scholar
  110. 110.
    Puissant F et al (1987) Embryo scoring as a prognostic tool in IVF treatment. Hum Reprod 2:705–708PubMedGoogle Scholar
  111. 111.
    Giorgetti C et al (1995) Embryo score to predict implantation after in – vitro fertilization: based on 957 single embryo transfers. Hum Reprod 10(9):2427–2431PubMedCrossRefGoogle Scholar
  112. 112.
    Ziebe S et al (1997) Embryo morphology or cleavage stage: how to select the best embryos for transfer after in-vitro fertilization. Hum Reprod 10(9):2427–2431Google Scholar
  113. 113.
    Staessen C et al (1998) Genetic constitution of multinuclear blastomeres and their derivative daughter blastomeres. Hum Reprod 13:1625–1631PubMedCrossRefGoogle Scholar
  114. 114.
    Van Royen E et al (2003) Multinucleation in cleavage stage embryos. Hum Reprod 18(5):1062–1069PubMedCrossRefGoogle Scholar
  115. 115.
    Jackson K et al (1998) Multinucleation in normally fertilized embryos is associated with an accelerated ovulation induction response and lower implantation and pregnancy rates in in vitro fertilization – embryo transfer cycles. Fertil Steril 70:60–66PubMedCrossRefGoogle Scholar
  116. 116.
    Kligman I et al (1996) The presence of multinucleated blastomeres in human embryos is correlated with chromosomal abnormalities. Hum Reprod 11:1492–1498PubMedCrossRefGoogle Scholar
  117. 117.
    Pickering S et al (1995) An analysis of multinucleated blastomere formation in human embryos. Hum Reprod 10:1912–1922PubMedGoogle Scholar
  118. 118.
    Laverge H et al (1997) Triple colour fluorescent in-situ- hybridization for chromosomes X, Y and 1 on spare human embryos. Hum Reprod 12:1492–1498Google Scholar
  119. 119.
    Alikani M et al (2000) Cleavage anomalies in early human embryos and survival after prolonged culture in-vitro. Hum Reprod 15:2634–2643PubMedCrossRefGoogle Scholar
  120. 120.
    Levy R et al (1998) Laser scanning confocal imaging of abnormal arrested human preimplantation embryos. J Assist Reprod Genet 15:485–495PubMedCentralPubMedCrossRefGoogle Scholar
  121. 121.
    Gerris J et al (1999) Prevention of twin pregnancy after in-vitro fertilization or intracytoplasmic sperm injection based on strict embryo criteria: a prospective randomized clinical trial. Hum Reprod 14:2581–2587PubMedCrossRefGoogle Scholar
  122. 122.
    Pelinck M et al (1998) Embryos cultured in vitro with multinucleated blastomeres have poor implantation potential in-vitro fertilization and intracytoplasmic sperm injection. Hum Reprod 13:960–963PubMedCrossRefGoogle Scholar
  123. 123.
    Van Royen E et al (2001) Calculating the implantation potential of day 3 embryos in women younger than 38 years of age: a new model. Hum Reprod 16(2):326–332PubMedCrossRefGoogle Scholar
  124. 124.
    Gerris J et al (2002) Elective single day 3 embryo transfer halves the twinning rate without decrease in the ongoing pregnancy rate of an IVF/ICSI programme. Hum Reprod 17:2626–2631PubMedCrossRefGoogle Scholar
  125. 125.
    Edwards R et al (1981) The growth of human preimplantation embryos in vitro. Am J Obstet Gynecol 141(4):408–416PubMedGoogle Scholar
  126. 126.
    Roux C et al (1995) Morphometric parameters of living human in-vitro fertilized embryos: importance of the asynchronous division process. Hum Reprod 10:1201–1207PubMedGoogle Scholar
  127. 127.
    Hiragi T et al (2005) Mechanisms of first cleavage specification in the mouse egg: is our body plan set at day 0? Cell Cycle 4:661–664CrossRefGoogle Scholar
  128. 128.
    Gardener R et al (2006) An investigation of the origin and significance of bilateral symmetry of the pronuclear zygote in the mouse. Hum Reprod 21:492–502CrossRefGoogle Scholar
  129. 129.
    Dokras A et al (1993) Human blastocyst grading: an indicator of developmental potential. Hum Reprod 8:2119–2127PubMedGoogle Scholar
  130. 130.
    Shapiro B et al (2000) Predictive value of 72-hr blastomere cell number on blastocyst development and success of subsequent transfer based on the degree of blastocyst development. Fertil Steril 73:582–586PubMedCrossRefGoogle Scholar
  131. 131.
    Langley M et al (2001) Extended embryo culture in human assisted reproduction treatments. Hum Reprod 16(5):902–908PubMedCrossRefGoogle Scholar
  132. 132.
    Magli M et al (1998) Incidence of chromosomal abnormalities from a morphologically normal cohort of embryos in poor-prognosis patients. J Assist Reprod Genet 15(5):297–301PubMedCentralPubMedCrossRefGoogle Scholar
  133. 133.
    Hnida C et al (2004) Computer-controlled, multilevel, morphometric analysis of blastomere size as biomarker of fragmentation and multinuclearity in human embryos. Hum Reprod 19:288–293PubMedCrossRefGoogle Scholar
  134. 134.
    Carrell D et al (2009) A simplified coculture system using homologous attached cumulus tissue results in improved human embryo morphology and pregnancy rates during in vitro fertilization. J Assist Reprod Genet 16(7):344–349CrossRefGoogle Scholar
  135. 135.
    Antczak M et al (1999) Temporal and spatial aspects of fragmentation in early human embryos: possible effects on developmental competence and association with the differential elimination of regulatory proteins from polarized domains. Hum Reprod 14:429–447PubMedCrossRefGoogle Scholar
  136. 136.
    Juriscova A et al (1996) Programmed cell death and human embryo fragmentation. Mol Hum Reprod 2(2):93–98CrossRefGoogle Scholar
  137. 137.
    Perez G et al (1999) Fragmentation and death (a.k.a. apoptosis) of ovulated oocytes. Mol Hum Reprod 5(5):414–420PubMedCrossRefGoogle Scholar
  138. 138.
    Alikani M et al (1999) Human embryo fragmentation in vitro and its implications for pregnancy and implantation. Fertil Steril 71:836–842PubMedCrossRefGoogle Scholar
  139. 139.
    Racowsky C et al (2003) Human embryo fragmentation in vitro and its implications for pregnancy and implantation. Fertil Steril 71:836–842Google Scholar
  140. 140.
    Hardy K et al (2003) Maintenance of the inner cell mass in human blastocysts from fragmented embryos. Biol Reprod 68(40):1165–1169PubMedGoogle Scholar
  141. 141.
    Van Blerkom J et al (2001) A microscopic and biochemical study of fragmentation phenotypes in stage-appropriate human embryos. Hum Reprod 16:719–729PubMedCrossRefGoogle Scholar
  142. 142.
    Sathanathan H et al (1988) The effects of cooling human oocytes. Hum Reprod 3:968–977Google Scholar
  143. 143.
    Plachot M et al (1987) Chromosome analysis of ovocytes and human embryos collected after fertilization in vitro. A model of natural selection against aneuploidy. Rev Fr Gynecol Obstet 83(910):613–617Google Scholar
  144. 144.
    Pellestor F et al (1994) Relationship between morphology and chromosomal constitution in human preimplantation embryo. Mol Reprod Dev 39(2):141–146PubMedCrossRefGoogle Scholar
  145. 145.
    Steer C et al (1992) The cumulative embryo score: a predictive embryo scoring technique to select the optimal number of embryos to transfer in an in-vitro fertilization and embryo transfer programme. Hum Reprod 7:117–119PubMedGoogle Scholar
  146. 146.
    Tan S et al (1992) Cumulative conception and live birth rates after in-vitro fertilization. Lancet 339:1390–1394PubMedCrossRefGoogle Scholar
  147. 147.
    Desai N et al (2000) Morphological evaluation of human embryos and derivation of an embryo quality scoring system specific for day 3 embryos: a preliminary study. Hum Reprod 15(10):2190–2196PubMedCrossRefGoogle Scholar
  148. 148.
    Dawson K et al (1995) Delaying transfer to the third day post-insemination, to select nonarrested embryos, increases development to the fetal heart stage. Hum Reprod 10:177–182PubMedCrossRefGoogle Scholar
  149. 149.
    Jones G et al (1998) Factors affecting the success of human blastocyst development and pregnancy following in vitro fertilization and embryo transfer. Fertil Steril 70(6):1022–1029PubMedCrossRefGoogle Scholar
  150. 150.
    Carillo A et al (1998) Improved clinical outcomes for in vitro fertilization with delay of embryo transfer from 48 to 72 hours after oocyte retrieval: use of glucose and phosphate free media. Fertil Steril 69:329–334CrossRefGoogle Scholar
  151. 151.
    Ebner T et al (2001) Embryo fragmentation in vitro and its impact on treatment and pregnancy outcome. Fertil Steril 76:281–285PubMedCrossRefGoogle Scholar
  152. 152.
    Skiadas CC et al (2006) Early compaction on day 3 may be associated with increased implantation potential. Fertil Steril 86(5):1386–1391PubMedCrossRefGoogle Scholar
  153. 153.
    Fiel D et al (2008) Day 4 embryo selection is equal to Day 5 using a new embryo scoring system validated in single embryo transfers. Hum Reprod 23(7):1505–1510CrossRefGoogle Scholar
  154. 154.
    della Ragione T et al (2007) Developmental stage on day-5 and fragmentation rate on day-3 can influence the implantation potential of top-quality blastocysts in IVF cycles with single embryo transfer. Reprod Biol Endocrinol 5:2PubMedCentralPubMedCrossRefGoogle Scholar
  155. 155.
    Gardner R et al (2000) Flow of cells from polar to mural trophectoderm is polarized in the mouse blastocyst. Hum Reprod 15:694–701PubMedCrossRefGoogle Scholar
  156. 156.
    Rijinder P et al (1998) The predictive value of day 3 embryo morphology regarding blastocyst formation, pregnancy and implantation rate after day 5 transfer following in-vitro fertilization or intracytoplasmic sperm injection. Hum Reprod 13:2869–2873CrossRefGoogle Scholar
  157. 157.
    Graham J et al (2000) Day 3 morphology is a poor predictor of blastocyst quality in extended culture. Fertil Steril 74:495–497PubMedCrossRefGoogle Scholar
  158. 158.
    Milki A et al (2002) Accuracy of day 3 criteria for selecting the best embryo. Fertil Steril 77:1191–1195PubMedCrossRefGoogle Scholar
  159. 159.
    Janny L et al (1994) Evidence for a strong paternal effect on human preimplantation embryo development and blastocyst formation. Mol Reprod Dev 38:36–42PubMedCrossRefGoogle Scholar
  160. 160.
    Miller J et al (2001) The effect of intracytoplasmic sperm injection and semen parameters on blastocyst development in vitro. Hum Reprod 16:918–924PubMedCrossRefGoogle Scholar
  161. 161.
    Seli E et al (2002) The extent of nuclear DNA damage in ejaculated spermatozoa impacts on blastocyst development after IVF. Fertil Steril 78(Suppl 1):S61CrossRefGoogle Scholar
  162. 162.
    Johnson M et al (1981) The foundation of two distinct cell lineages within mouse morula. Cell 24:71–80PubMedCrossRefGoogle Scholar
  163. 163.
    Racowsky C et al (2000) The number of eight-cell embryos is a key determinant for selecting day 3 or day 5 transfer. Fertil Steril 73:558–564PubMedCrossRefGoogle Scholar
  164. 164.
    Richter K et al (2001) Quantitative grading of a human blastocyst: optimal inner cell mass size and shape. Fertil Steril 76(6):1157–1167PubMedCrossRefGoogle Scholar
  165. 165.
    Balaban B et al (2000) Blastocyst quality affects the success of blastocyst-stage embryo transfer. Fertil Steril 74:282–287PubMedCrossRefGoogle Scholar
  166. 166.
    Gardner D et al (1999) In-vitro culture of human blastocysts. In: Jansen R, Mortimer D (eds) Towards reproductive certainty: fertility and genetics beyond 1999. Parthenon, Carnforth, pp 378–388Google Scholar
  167. 167.
    Racowsky C et al (2009) Is there an advantage in scoring early embryos on more than one day? Hum Reprod 24(9):2104–2113PubMedCentralPubMedCrossRefGoogle Scholar
  168. 168.
    Fisch J et al (2003) The graduated embryo score predicts the outcome of assisted reproductive technologies better then a single day 3 evaluation and achieves results associated with blastocyst transfer from day 3 embryo transfer. Fertil Steril 80(6):1352–1358PubMedCrossRefGoogle Scholar
  169. 169.
    Sjoblom P et al (2006) Prediction of embryo developmental potential and pregnancy based on early stage morphological characteristics. Fertil Steril 86:848–861PubMedCrossRefGoogle Scholar
  170. 170.
    Terriou P et al (2001) Embryo score is a better predictor of pregnancy than the number of transferred embryos or female age. Fertil Steril 75:525–531PubMedCrossRefGoogle Scholar
  171. 171.
    Holte J et al (2007) Construction of an evidence-based integrated morphology cleavage embryo score for implantation potential of embryos scored and transferred on Day 2 after oocyte retrieval. Hum Reprod 22:548–557PubMedCrossRefGoogle Scholar
  172. 172.
    Vergouw C et al (2008) Metabolomic profiling by near-infrared spectroscopy as a tool to assess embryo viability: a novel, non-invasive method for embryo selection. Hum Reprod 23:1499–1504PubMedCrossRefGoogle Scholar
  173. 173.
    Saith R et al (1998) Relationships between the developmental potential of human in-vitro fertilization embryos and features describing the embryo, oocyte and follicle. Hum Reprod 4:121–134CrossRefGoogle Scholar
  174. 174.
    Jurisica I et al (1998) Case-based reasoning in IVF: prediction and knowledge mining. Artif Intell Med 12:1–24PubMedCrossRefGoogle Scholar
  175. 175.
    Trimarchi J et al (2003) Comparing data mining and logistic regression for predicting IVF outcome. Fertil Steril 80:S100CrossRefGoogle Scholar
  176. 176.
    Patrizi G et al (2004) Pattern recognition methods in human-assisted reproduction. Int Trans Oper Res 11:365–379CrossRefGoogle Scholar
  177. 177.
    Fisch J et al (2001) The Graduated Embryo Score (GES) predicts blastocyst formation and pregnancy rate from cleavage-stage embryos. Hum Reprod 16(9):1970–1975PubMedCrossRefGoogle Scholar
  178. 178.
    Fisch J et al (2006) Graduated Embryo score and soluble human leukocyte antigen-expression improve assisted reproductive technology outcomes and suggest a basis for elective single-embryo transfer. Fertil Steril 87(4):757–763CrossRefGoogle Scholar
  179. 179.
    Neuber E et al (2003) Sequential assessment of individually cultured human embryos as an indicator of subsequent good quality blastocyst development. Hum Reprod 18:1307–1312PubMedCrossRefGoogle Scholar
  180. 180.
    Neuber E et al (2006) Sequential embryo assessment investigator – driven morphological assessment at selecting a good quality blastocyst. Fertil Steril 85(3):794–796PubMedCrossRefGoogle Scholar
  181. 181.
    Rienzi L et al (2002) Day 3 embryo transfer with combined evaluation at the pronuclear and embryo stages compares favourably with day 5 blastocyst transfer. Hum Reprod 17:1852–1855PubMedCrossRefGoogle Scholar
  182. 182.
    Carrell D et al (1999) A simplified coculture system using homologous attached cumulus tissue results in improved human embryo morphology and pregnancy rates during in vitro fertilization. J Assist Reprod Genet 16(7):344–349PubMedCentralPubMedCrossRefGoogle Scholar
  183. 183.
    Hunault C et al (2002) A prediction model for selecting patients undergoing in vitro fertilization for selecting patients undergoing in vitro fertilization for elective single embryo transfer. Fertil Steril 77(40):725–732PubMedCrossRefGoogle Scholar
  184. 184.
    James A et al (2006) The limited importance of pronuclear scoring of human zygotes. Hum Reprod 21(6):1599–1604PubMedCrossRefGoogle Scholar

Copyright information

© Springer Science+Business Media New York 2014

Authors and Affiliations

  1. 1.Division of Reproductive Endocrinology and Infertility, Department of OB/GYNStanford UniversityStanfordUSA

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