title: Opinions and practice patterns of obstetricians-gynecologists in the United States regarding amniocentesis in twins.
abstract: OBJECTIVE
  Accurate amniocentesis-related pregnancy loss (ARL) rates for twin gestations remains elusive because of varying ARL definitions in the literature. We examined how OB/GYNs define/counsel women carrying twins about ARL.
  
  
  METHODS
  A random sample of 1000 American College of OB/GYN (ACOG) fellows and ACOG Collaborative Ambulatory Research Network (CARN) members were mailed surveys about their opinions/practice patterns regarding amniocentesis in twins. There were 208/400 (52%) CARN members and 166/600 (27%) ACOG fellows who returned the survey (37% response rate).
  
  
  RESULTS
  Of respondents, 80.8% practiced general OB/GYN, and 9.1% practiced maternal fetal medicine. Of respondents, 72% discussed amniocentesis for prenatal diagnosis. Of these, 91.7% discuss the risk of ARL; however, 47.4% do not quote an ARL rate. Of those who discuss ARL rates, 65% quote a rate greater than for singletons. Regarding monochorionic-diamniotic twins, 12.1% of respondents said the ARL rate was less, 39.6% said equal to, and 38.9% said greater than for dichorionic twins. Table 1 lists the most common clinical definitions/time intervals used to describe ARL.
  
  
  CONCLUSIONS
  Various definitions/ARL rates are used when counseling about ARL in twins. Further studies using a widely accepted definition of ARL are necessary to improve the counseling of women considering amniocentesis for prenatal diagnosis in twins.
authors.affiliation: Obstetrics and Gynecology, Division of Maternal Fetal Medicine, Columbia University Medical Center, New York, NY, USA. jyv2101@mail.cumc.columbia.edu
authors.forename: Joy
authors.initials: J
authors.lastname: Vink
authors.forename: Britta
authors.initials: B
authors.lastname: Anderson
authors.forename: Karin
authors.initials: K
authors.lastname: Fuchs
authors.forename: Jay
authors.initials: J
authors.lastname: Schulkin
authors.forename: Mary E
authors.initials: ME
authors.lastname: D'Alton
mesh_terms: D000328:Adult; D000649:Amniocentesis / Q000706:statistics & numerical data; D003625:Data Collection; D005104:Expert Testimony; D005260:Female; D006176:Gynecology / Q000706:statistics & numerical data; D006801:Humans; D008297:Male; D008875:Middle Aged; D009774:Obstetrics / Q000706:statistics & numerical data; D010818:Practice Patterns, Physicians' / Q000706:statistics & numerical data*; D011247:Pregnancy; D059285:Pregnancy, Twin / Q000706:statistics & numerical data; D014427:Twins; D014481:United States / Q000453:epidemiology