title: [Complication rates after amniocentesis in twin pregnancies: a case control study and review of the literature].
abstract: BACKGROUND
  Twin pregnancies nave a nigner risk of fetal malformation than singleton pregnancies. The literature suggests a higher risk of fetal loss associated to amniocentesis in twin pregnancies compared to singleton ones. However, published studies are very heterogeneous, rarely controlled or are not taking into account many confounding factors.
  
  
  METHODS
  To assess all complications that can be associated with amniocentesis in twin pregnancies.
  
  
  METHODS
  We collected retrospectively medical data concerning twin pregnancies that underwent an amniocentesis in Erasme and Edith Cavell (IMEC) hospitals in Brussels since February 2002. We compared all the complications to those of twin pregnancies that haven't undertaken amniocentesis and singleton pregnancies that underwent amniocentesis. The cases and control groups were matched for age, parity and gestational age at the time of amniocentesis.
  
  
  RESULTS
  94 cases of twin pregnancies that underwent amniocentesis (group I) were included and compared to 94 twin pregnancies that haven't undertaken amniocentesis and 94 singleton pregnancies that underwent amniocentesis. The rate of intra-uterine growth restriction and pregnancies obtained by assisted reproductive medicine was significantly higher in the group I for the latter, the rate of late miscarriage was 2.1%, the rate of overall foetal loss is 2.68%, the rate of overall preterm birth ≤ 37 SA was 59.3% (6.4% ≤ 28 SA and 29.8% ≤ 34 SA). These complications were not significantly higher than those of the control groups after multivariable logistic regression analysis.
  
  
  CONCLUSIONS
  Our data showed no increased risk of foetal loss or preterm birth among twins that underwent amniocentesis compared to controls.
authors.forename: A
authors.initials: A
authors.lastname: Sassi
authors.forename: C
authors.initials: C
authors.lastname: Donner
mesh_terms: D000328:Adult; D000649:Amniocentesis / Q000009:adverse effects*; D001530:Belgium; D016022:Case-Control Studies; D005260:Female; D006801:Humans; D011247:Pregnancy; D059285:Pregnancy, Twin; D012189:Retrospective Studies