title: Preimplantation genetics: chromosomes of fragmented human embryos.
abstract: OBJECTIVE
  To examine the chromosome makeup of fragmented human embryos.
  
  
  METHODS
  Prospective.
  
  
  METHODS
  Assisted reproductive technology (ART) program.
  
  
  METHODS
  One hundred twenty-one poor-quality embryos from 58 patients 31 to 40 years of age admitted for an ART program were examined for chromosome makeup.
  
  
  RESULTS
  Chromosome anomalies were observed in 31.9% (29/91) of poor-quality embryos, 19.8% (18/91) displayed mosaicism (diploid/haploid, diploid/triploid, diploid/aneuploid), 5.5% (5/91) showed polyploidy, 2.2% (2/91) had pulverized chromosomes, 2.2% (2/91) revealed aneuploidy, 1.1% (1/91) had prematurely condensed chromosomes, and 1.1% (1/91) had structural rearrangements involving chromosome number 2. The mean age of patients showing anomalies (36.5 years) was not significantly higher than the mean for the entire group (35.5 years).
  
  
  CONCLUSIONS
  The incidence of chromosome anomalies in fragmented human embryos is high. These anomalies originate either in the gametes or through mitotic nondisjunction within the embryos. It is not advisable to replace such embryos into patients going through in vitro fertilization.
authors.affiliation: Department of Obstetrics and Gynaecology, National University of Singapore.
authors.forename: A
authors.initials: A
authors.lastname: Bongso
authors.forename: S C
authors.initials: SC
authors.lastname: Ng
authors.forename: J
authors.initials: J
authors.lastname: Lim
authors.forename: C Y
authors.initials: CY
authors.lastname: Fong
authors.forename: S
authors.initials: S
authors.lastname: Ratnam
mesh_terms: D000328:Adult; D002869:Chromosome Aberrations; D004622:Embryo, Mammalian / Q000648:ultrastructure*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D007246:Infertility / Q000628:therapy; D009630:Nondisjunction, Genetic; D011003:Ploidies; D011247:Pregnancy; D011446:Prospective Studies