title: Number of supernumerary vitrified blastocysts is positively correlated with implantation and live birth in single-blastocyst embryo transfers.
abstract: OBJECTIVE
  To estimate whether live birth in single-blastocyst transfers is correlated with the number of sibling supernumerary vitrified blastocysts (embryos not transferred) generated from that same cycle.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  A large academic assisted reproduction clinic.
  
  
  METHODS
  All single-blastocyst transfers in 2010 graded as "good" embryos by Society for Assisted Reproductive Technologies (SART) criteria.
  
  
  METHODS
  None.
  
  
  METHODS
  Implantation and live birth.
  
  
  RESULTS
  Of the 655 single-blastocyst transfers that met inclusion criteria, implantation occurred in 65% and live birth in 54% of cycles. In chi-square analysis, patients with supernumerary vitrified blastocysts had a statistically higher implantation rate (65% versus 50%) and live-birth rate (56% versus 41%) when compared with patients without supernumerary blastocysts. Univariate logistic regression demonstrated an increase in implantation (OR 1.09; 95% CI, 1.03-1.15) and live birth (OR 1.06; 95% CI, 1.02-1.09) with increasing number of supernumerary blastocysts. Multivariate logistic regression analysis demonstrated that patient age and the number of supernumerary blastocysts were statistically significantly associated with implantation and live birth.
  
  
  CONCLUSIONS
  The number of supernumerary vitrified blastocysts correlated positively with the odds of implantation and live birth in good quality single-blastocyst transfers. Patients with supernumerary blastocysts are good candidates for single-embryo transfer.
authors: Program in Reproductive and Adult Endocrinology, Eunice Kennedy Shriver National Institute of Child Health and Human Development, National Institutes of Health, Bethesda, Maryland 20892, USA.
authors: Micah J
authors: MJ
authors: Hill
authors: Kevin S
authors: KS
authors: Richter
authors: Ryan J
authors: RJ
authors: Heitmann
authors: Terrance D
authors: TD
authors: Lewis
authors: Alan H
authors: AH
authors: DeCherney
authors: James R
authors: JR
authors: Graham
authors: Eric
authors: E
authors: Widra
authors: Michael J
authors: MJ
authors: Levy
mesh_terms: D000328:Adult; D001755:Blastocyst / Q000502:physiology; D015331:Cohort Studies; D010064:Embryo Implantation / Q000502:physiology; D005260:Female; D006801:Humans; D050498:Live Birth / Q000453:epidemiology*; D011247:Pregnancy; D012189:Retrospective Studies; D056826:Single Embryo Transfer / Q000379:methods / Q000639:trends*; D058989:Vitrification