title: Assisted reproductive technologies: estimates of their contribution to multiple births and newborn hospital days in the United States.
abstract: OBJECTIVE
  Estimate the contribution of assisted reproductive technology (ART) in the United States to multiple gestation births and newborn hospital days.
  
  
  METHODS
  Analysis of successful ART conceptions occurring during 1990 to 1991 compared with vital statistics. Newborn hospital days are estimated from the 1990 National Hospital Discharge Survey.
  
  
  METHODS
  The American Fertility Society and the Society for Assisted Reproductive Technology registry.
  
  
  METHODS
  Infants delivered from ART.
  
  
  METHODS
  Assisted reproductive technology.
  
  
  METHODS
  Number of multiple gestation infants and newborn hospital days.
  
  
  RESULTS
  Approximately 12,327 live-born infants were delivered from ART conceptions during 1990 to 1991, representing 22.2% of all live-born triplet, 17.3% of quadruplet, and 11.4% of quintuplet infants born in the United States. The number of newborn hospital days attributed to ART infants was 87,135 days. Between the periods 1972 through 1974 and 1990 through 1991, the rate of triplet and higher order multiple gestation infants per 100,000 white live births increased by 191%, with 38% due to ART conceptions and 30% to increased childbearing among older women.
  
  
  CONCLUSIONS
  Assisted reproductive technology contributed 22% of U.S. triplet and higher order multiple births during 1990 to 1991.
authors.affiliation: Program Services and Development Branch, Centers for Disease Control and Prevention, Atlanta, Georgia 30341-3724, USA.
authors.forename: L S
authors.initials: LS
authors.lastname: Wilcox
authors.forename: J L
authors.initials: JL
authors.lastname: Kiely
authors.forename: C L
authors.initials: CL
authors.lastname: Melvin
authors.forename: M C
authors.initials: MC
authors.lastname: Martin
mesh_terms: D005260:Female; D005313:Fetal Death / Q000453:epidemiology; D006801:Humans; D007902:Length of Stay / Q000706:statistics & numerical data*; D011247:Pregnancy; D011272:Pregnancy, Multiple / Q000706:statistics & numerical data*; D012099:Reproductive Techniques; D014481:United States