title: Prediction of human blastocyst development from morulas with delayed and/or incomplete compaction.
abstract: OBJECTIVE
  To determine the influence of delayed compaction and fragmentation on the developmental capacity of morulas.
  
  
  METHODS
  Prospective study.
  
  
  METHODS
  University IVF center.
  
  
  METHODS
  Intracytoplasmic sperm injection (ICSI) cycles with compact embryos on day 4 or day 5.
  
  
  METHODS
  The embryos were divided into day 4 (n = 329) and day 5 (n = 256) morulas and graded I, II, or III, according to the percentage of fragmentation (<5%, 5%-20%, or >20%). The embryos were measured using Cronus3 software.
  
  
  METHODS
  Blastocyst development rate, blastocoel expansion rate, and optimal blastocyst rate. In an optimal blastocyst: surface area, trophectoderm cell number, inner cell mass (ICM) surface area, ICM volume and ICM shape.
  
  
  RESULTS
  Day 4 morulas in classes I-III developed into optimal blastocysts in 57.4%, 50%, and 35.6% of the total, respectively, and day 5 morulas in classes I-III in 43.3%, 29.1%, and 13.6% of the total, respectively. A negative association was identified between the amount of morula fragmentation, the blastocyst ICM size, and the number of trophectoderm cells. A delay of 1 day in compaction was associated with a reduced ICM volume.
  
  
  CONCLUSIONS
  The measurement of compaction timing and cytoplasmic loss in morulas assists in predicting their ability to develop into optimal blastocysts.
authors: Department of Reproductive Medicine and Gynecologic Endocrinology, University Medical Centre Maribor, Maribor, Slovenia. martin.ivec@ukc-mb.si
authors: Martin
authors: M
authors: Ivec
authors: Borut
authors: B
authors: Kovacic
authors: Veljko
authors: V
authors: Vlaisavljevic
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000166:cytology / Q000502:physiology*; D002452:Cell Count; D048430:Cell Shape; D002478:Cells, Cultured; D002970:Cleavage Stage, Ovum / Q000166:cytology / Q000473:pathology* / Q000502:physiology; D047108:Embryonic Development / Q000502:physiology*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007246:Infertility / Q000175:diagnosis / Q000473:pathology / Q000628:therapy; D008297:Male; D009028:Morula / Q000166:cytology / Q000378:metabolism* / Q000473:pathology / Q000502:physiology; D011247:Pregnancy; D011379:Prognosis; D013997:Time Factors