title: Does meiotic spindle normality predict improved blastocyst development, implantation and live birth rates?
abstract: OBJECTIVE
  To investigate the relationship between spindle normality and: 1) blastocyst formation; 2) implantation rates; and 3) live birth rates.
  
  
  METHODS
  Prospective observational study.
  
  
  METHODS
  A private fertility clinic.
  
  
  METHODS
  One hundred patients ≤40 years old undergoing intracytoplasmic sperm injection (ICSI).
  
  
  METHODS
  Meiotic spindles were imaged before ICSI with the use of Oosight microscopy. With the use of specific criteria, spindle normality was independently assessed by two researchers. Blastocysts were chosen for transfer by standard light microscopic morphologic criteria by researchers who were blinded to the spindle assessment.
  
  
  METHODS
  1) Blastocyst formation; 2) implantation; and 3) live birth rates.
  
  
  RESULTS
  A total of 808/920 oocytes were metaphase II. Of those, 711 (88%) had a visible spindle: 205 (29%) were normal spindles (NS) and 506 (71%) abnormal spindles (AS). Fertilization rates were significantly higher in NS oocytes. Although NS and AS oocytes both formed morphologically good-quality blastocysts, implantation and live birth rates were higher from NS oocytes. All ongoing pregnancies resulted from NS oocytes.
  
  
  CONCLUSIONS
  Spindle assessment with polarized light microscopy provides an early predictor of the pregnancy potential of that oocyte. AS oocytes can form good-quality blastocysts, but these appear to have little chance of live birth. Therefore, spindle assessment should improve the selection of the best embryo for single embryo transfer.
authors.affiliation: IVF Australia, Sydney, New South Wales, Australia. skilani@ivf.com.au
authors.forename: Suha
authors.initials: S
authors.lastname: Kilani
authors.forename: Simon
authors.initials: S
authors.lastname: Cooke
authors.forename: Liza
authors.initials: L
authors.lastname: Tilia
authors.forename: Michael
authors.initials: M
authors.lastname: Chapman
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000648:ultrastructure*; D010064:Embryo Implantation; D047108:Embryonic Development; D005260:Female; D006801:Humans; D007246:Infertility / Q000503:physiopathology / Q000628:therapy*; D050498:Live Birth; D008540:Meiosis; D008859:Microscopy, Polarization; D009517:New South Wales; D015588:Observer Variation; D054315:Oocyte Retrieval; D010062:Ovulation Induction; D011237:Predictive Value of Tests; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D015203:Reproducibility of Results; D056826:Single Embryo Transfer; D020554:Sperm Injections, Intracytoplasmic; D008941:Spindle Apparatus / Q000648:ultrastructure*; D016896:Treatment Outcome; D055815:Young Adult