title: Morphologic grading of euploid blastocysts influences implantation and ongoing pregnancy rates.
abstract: To determine whether blastocyst grading can predict pregnancy outcomes in the frozen-thawed embryo transfer (FET) of euploid blastocysts.
  
  
  
  Retrospective cohort study.
  
  
  
  Academic medical center.
  
  
  
  Women who underwent FET of euploid embryo(s) between January 2013 and December 2015, with blastocysts were divided into four groups based on their morphologic grading before cryopreservation: excellent (≥3AA), good (3-6AB, 3-6BA, 1-2AA), average (3-6BB, 3-6AC, 3-6CA, 1-2AB, 1-2BA), and poor (1-6BC, 1-6CB, 1-6CC, 1-2BB).
  
  
  
  FET.
  
  
  
  Ongoing pregnancy rate (OPR).
  
  
  
  A total of 417 FET cycles (477 embryos) were included. Excellent-quality embryos (n = 38) yielded a statistically significantly higher OPR than poor-quality embryos (n = 106) (84.2% vs. 35.8%; adjusted odds ratio 11.0; 95% confidence interval, 3.8-32.1) and average-quality embryos (n = 197) (84.2% vs. 55.8%; adjusted odds ratio 4.8; 95% confidence interval, 1.7-13.3). Good-quality embryos (n = 76) were associated with a statistically significantly higher OPR than poor-quality embryos (61.8% vs. 35.8%). These odds ratios were adjusted for patient's age, body mass index, number of transferred embryos, type of frozen cycle, peak endometrial thickness, day of trophectoderm biopsy (5 or 6), and total number of euploid embryos for each patient. An inner cell mass grade of A yielded a statistically significantly higher OPR than ICM grade C (76.2% vs. 13.5%) or grade B (76.2% vs. 53.6%) after controlling for all confounders.
  
  
  
  Contrary to prior published studies, the current data suggest that blastocyst morphologic grading and particularly inner cell mass grade is a useful predictor of OPR per euploid embryo. Morphologic grading should be used to help in the selection among euploid blastocysts.
authors.affiliation: The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, New York.
authors.forename: Mohamad
authors.initials: M
authors.lastname: Irani
authors.affiliation: The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, New York. Electronic address: der2005@med.cornell.edu.
authors.forename: David
authors.initials: D
authors.lastname: Reichman
authors.affiliation: Department of Obstetrics and Gynecology, Weill Cornell Medicine, New York, New York.
authors.forename: Alex
authors.initials: A
authors.lastname: Robles
authors.affiliation: The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, New York.
authors.forename: Alexis
authors.initials: A
authors.lastname: Melnick
authors.affiliation: The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, New York.
authors.forename: Owen
authors.initials: O
authors.lastname: Davis
authors.affiliation: The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, New York.
authors.forename: Nikica
authors.initials: N
authors.lastname: Zaninovic
authors.affiliation: The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, New York.
authors.forename: Kangpu
authors.initials: K
authors.lastname: Xu
authors.affiliation: The Ronald O. Perelman and Claudia Cohen Center for Reproductive Medicine, Weill Cornell Medicine, New York, New York.
authors.forename: Zev
authors.initials: Z
authors.lastname: Rosenwaks
mesh_terms: D000328:Adult; D001706:Biopsy; D001755:Blastocyst / Q000473:pathology*; D053624:Blastocyst Inner Cell Mass / Q000473:pathology; D015925:Cryopreservation; D046149:Embryo Culture Techniques; D010064:Embryo Implantation; D004624:Embryo Transfer / Q000009:adverse effects; D005260:Female; D005298:Fertility; D005307:Fertilization in Vitro / Q000009:adverse effects; D006801:Humans; D007246:Infertility / Q000175:diagnosis / Q000503:physiopathology / Q000628:therapy*; D011003:Ploidies; D011237:Predictive Value of Tests; D011247:Pregnancy; D018873:Pregnancy Rate; D012189:Retrospective Studies; D012307:Risk Factors; D016896:Treatment Outcome
keywords: Blastocyst morphologic grading; IVF outcome; PGS; euploid embryo; inner cell mass; preimplantation genetic screening