title: Spontaneous embryonic loss rates in twin and singleton pregnancies after transfer of top- versus intermediate-quality embryos.
abstract: OBJECTIVE
  To determine whether embryo quality is associated with early spontaneous loss rates in twin and singleton pregnancies after IVF/intracytoplasmic sperm injection (ICSI).
  
  
  METHODS
  Retrospective, single center analysis.
  
  
  METHODS
  The Center of Reproductive Medicine, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy.
  
  
  METHODS
  Women undergoing IVF/ICSI and two- or three-embryo transfer of intermediate- and top-quality embryos.
  
  
  METHODS
  First-trimester sonography at 6 to 7 weeks to determine number of embryos with positive heartbeat. Number of embryos lost was calculated from a second-trimester sonogram.
  
  
  METHODS
  Rates of total pregnancy loss, as related to embryo quality, initial number of embryos, maternal age <35 or > or =35 years, and IVF procedure.
  
  
  RESULTS
  A total of 94 losses (23.1% of 407 pregnancies) were counted, with similar proportions in pregnancies after transfer of intermediate- or top-quality embryos. Neither the mode of IVF procedure nor the number of transferred embryos affected the loss rate. In contrast, the loss rate was significantly higher in older mothers after transfer of intermediate-quality embryos (odds ratio [OR 2.4], 95% confidence interval [CI] 1.1-5.5). Losses among singletons were significantly higher compared with losses among twins (OR 2.5, 95% CI 1.1-6.0), but this was observed in top-quality embryos only.
  
  
  CONCLUSIONS
  Top-quality but not intermediate-quality ETs are associated with lower early spontaneous loss rates among twin pregnancies after IVF/ICSI.
authors.affiliation: Department of Obstetrics and Gynecology, Arcispedale Santa Maria Nuova, Reggio Emilia, Italy.
authors.forename: Giovanni B
authors.initials: GB
authors.lastname: La Sala
authors.forename: Alessia
authors.initials: A
authors.lastname: Nicoli
authors.forename: Maria Teresa
authors.initials: MT
authors.lastname: Villani
authors.forename: Andrea
authors.initials: A
authors.lastname: Gallinelli
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Nucera
authors.forename: Isaac
authors.initials: I
authors.lastname: Blickstein
mesh_terms: D000022:Abortion, Spontaneous / Q000453:epidemiology*; D000328:Adult; D001755:Blastocyst; D004624:Embryo Transfer / Q000592:standards* / Q000706:statistics & numerical data; D005260:Female; D006801:Humans; D008423:Maternal Age; D011247:Pregnancy; D011256:Pregnancy Outcome / Q000453:epidemiology*; D011261:Pregnancy Trimester, First; D011272:Pregnancy, Multiple / Q000706:statistics & numerical data; D012189:Retrospective Studies; D020554:Sperm Injections, Intracytoplasmic / Q000592:standards* / Q000706:statistics & numerical data; D014427:Twins