title: Elective single embryo transfer trends and predictors of a good perinatal outcome--United States, 1999 to 2010.
abstract: OBJECTIVE
  To assess trends in elective single ET and identify factors associated with a good perinatal outcome.
  
  
  METHODS
  Retrospective cohort study.
  
  
  METHODS
  Clinic-based data.
  
  
  METHODS
  A total of 886,686 fresh, nondonor cycles reported to the National Assisted Reproductive Technology Surveillance System during 1999-2010, of which 17,166 met criteria for elective single ET.
  
  
  METHODS
  None.
  
  
  METHODS
  Rates of elective single ET and good perinatal outcome (term, singleton infant with normal birth weight).
  
  
  RESULTS
  In 2010, elective single ET comprised 5.6% of all fresh transfers, representing an eightfold increase since publication of first guidelines in 2004 recommending elective single ET. Compared with other ETs, elective single ETs were nearly twice as likely to result in a good perinatal outcome (37.1% vs. 18.9%, respectively). Among women using elective single ET, those aged <35 and 35-37 years had a good perinatal outcome (40.2% and 32.5%, respectively). In multivariable, log-binomial analyses, factors positively associated with a good perinatal outcome included male factor infertility, day 5 ET, and having ≥3 supernumerary embryos for cryopreservation.
  
  
  CONCLUSIONS
  Between 1999 and 2010, national rates of elective single ET increased. Given the frequency of good perinatal outcomes among women aged 35-37 years, guidelines for elective single ET could be expanded to include patients in this age group with favorable prognoses.
authors: Department of Gynecology and Obstetrics, Emory University School of Medicine, Atlanta, Georgia, USA. MLStei2@emory.edu
authors: Marissa L
authors: ML
authors: Steinberg
authors: Sheree
authors: S
authors: Boulet
authors: Dmitry
authors: D
authors: Kissin
authors: Lee
authors: L
authors: Warner
authors: Denise J
authors: DJ
authors: Jamieson
mesh_terms: D000328:Adult; D000367:Age Factors; D001724:Birth Weight; D016009:Chi-Square Distribution; D015925:Cryopreservation; D005260:Female; D005307:Fertilization in Vitro; D019538:Health Care Surveys; D006801:Humans; D007231:Infant, Newborn; D007247:Infertility, Female / Q000453:epidemiology / Q000628:therapy*; D007248:Infertility, Male / Q000453:epidemiology / Q000628:therapy*; D050498:Live Birth; D008297:Male; D015999:Multivariate Analysis; D016017:Odds Ratio; D018579:Patient Selection; D017410:Practice Guidelines as Topic; D011247:Pregnancy; D012189:Retrospective Studies; D056826:Single Embryo Transfer / Q000592:standards / Q000639:trends*; D013997:Time Factors; D016896:Treatment Outcome; D014481:United States / Q000453:epidemiology