title: Amniocentesis and chorionic villus sampling in twin gestations: which is the best sampling technique?
abstract: OBJECTIVE
  To compare the fetal loss rate <24 weeks and the preterm premature rupture of the membranes <34 weeks' gestation according to type of invasive procedure and to sampling techniques in twins.
  
  
  METHODS
  Retrospective cohort study of 204 twin pregnancies, who underwent amniocentesis (100) or chorionic villus sampling (104).
  
  
  RESULTS
  Fetal loss rate <4 weeks was 3.85% in chorionic villus sampling group and 4.00% in amniocentesis group (P value not significant). According to sampling technique, fetal loss rate was 4.17% (chorionic villus sampling 1 puncture), 2.70% (amniocentesis 1 puncture), 3.75% (chorionic villus sampling 2 punctures), and 4.76% (amniocentesis 2 punctures), (P values not significant). Preterm premature rupture of the membranes rate <34 weeks was 8.2% chorionic villus sampling group and 10% in amniocentesis group (P value not significant). According to sampling technique, preterm premature rupture of the membranes rate was 12.5% (chorionic villus sampling 1 puncture), 8.1% (amniocentesis 1 puncture), 6.9% (chorionic villus sampling 2 punctures), and 11.1 % (amniocentesis 2 punctures), (P values not significant).
  
  
  CONCLUSIONS
  Double entry technique does not affect significantly the outcomes evaluated, in both amniocentesis and chorionic villus sampling.
authors.affiliation: Department of Obstetrics and Gynecology, St. Orsola Malpighi Hospital, University of Bologna, Bologna, Italy.
authors.forename: Giuliana
authors.initials: G
authors.lastname: Simonazzi
authors.forename: Alessandra
authors.initials: A
authors.lastname: Curti
authors.forename: Antonio
authors.initials: A
authors.lastname: Farina
authors.forename: Gianluigi
authors.initials: G
authors.lastname: Pilu
authors.forename: Luciano
authors.initials: L
authors.lastname: Bovicelli
authors.forename: Nicola
authors.initials: N
authors.lastname: Rizzo
mesh_terms: D000328:Adult; D000649:Amniocentesis / Q000009:adverse effects / Q000706:statistics & numerical data*; D015193:Chorionic Villi Sampling / Q000009:adverse effects / Q000706:statistics & numerical data*; D015331:Cohort Studies; D005260:Female; D005313:Fetal Death / Q000453:epidemiology*; D005322:Premature Rupture of Fetal Membranes / Q000453:epidemiology*; D006801:Humans; D053208:Kaplan-Meier Estimate; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011262:Pregnancy Trimester, Second; D012189:Retrospective Studies; D014427:Twins