title: The impact of assisted reproductive technology and chorionicity in twin pregnancies complicated by obstetric cholestasis.
abstract: OBJECTIVE
  To assess in a cohort of twin pregnancies the prevalence of obstetric cholestasis (OC) and its correlation with the type of conception and chorionicity.
  
  
  METHODS
  A retrospective cohort study including all the twin pregnancies delivered between 2005 and 2013 at our University Hospital was carried out. In the study population, the prevalence of OC was investigated in relationship to the impact of assisted reproductive technology (ART) and of chorionicity.
  
  
  RESULTS
  Overall, 569 twin pregnancies were included in the study population. Among those complicated by OC, the rate of ART was 3-fold higher (OR 3.4, 95% CI 1.2-9.5, p = 0.02), whereas the rate of dichorionicity did not differ significantly (OR 1.6, 95% CI 0.3-7.9, p = 0.53).
  
  
  CONCLUSIONS
  The risk of developing OC seems to be significantly higher among twin pregnancies obtained after ART in comparison with those conceived spontaneously.
authors.affiliation: a Department of Obstetrics and Gynecology , Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Giuseppina
authors.initials: G
authors.lastname: Pacella
authors.affiliation: a Department of Obstetrics and Gynecology , Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Ginevra
authors.initials: G
authors.lastname: Salsi
authors.affiliation: a Department of Obstetrics and Gynecology , Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Tiziana
authors.initials: T
authors.lastname: Arcangeli
authors.affiliation: a Department of Obstetrics and Gynecology , Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Aly
authors.initials: A
authors.lastname: Youssef
authors.affiliation: a Department of Obstetrics and Gynecology , Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Antonio
authors.initials: A
authors.lastname: Farina
authors.affiliation: b Cardiology Unit-Department of Experimental, Diagnostic and Specialty Medicine, Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Maria Letizia
authors.initials: ML
authors.lastname: Bacchi-Reggiani
authors.affiliation: a Department of Obstetrics and Gynecology , Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Federica
authors.initials: F
authors.lastname: Bellussi
authors.affiliation: c Department of Digestive Diseases and Internal Medicine , S. Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy , and.
authors.forename: Giuseppe
authors.initials: G
authors.lastname: Mazzella
authors.affiliation: c Department of Digestive Diseases and Internal Medicine , S. Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy , and.
authors.forename: Francesco
authors.initials: F
authors.lastname: Azzaroli
authors.affiliation: a Department of Obstetrics and Gynecology , Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Eleonora
authors.initials: E
authors.lastname: Porcu
authors.affiliation: a Department of Obstetrics and Gynecology , Sant'Orsola-Malpighi Hospital, University of Bologna , Bologna , Italy .
authors.forename: Nicola
authors.initials: N
authors.lastname: Rizzo
authors.affiliation: d Department of Obstetrics and Gynecology , Maggiore Hospital, University of Parma , Parma, Italy.
authors.forename: Tullio
authors.initials: T
authors.lastname: Ghi
mesh_terms: D000328:Adult; D002780:Cholestasis, Intrahepatic / Q000453:epidemiology* / Q000209:etiology; D005260:Female; D006801:Humans; D007558:Italy / Q000453:epidemiology; D011247:Pregnancy; D011248:Pregnancy Complications / Q000453:epidemiology* / Q000209:etiology; D059285:Pregnancy, Twin / Q000706:statistics & numerical data*; D027724:Reproductive Techniques, Assisted / Q000009:adverse effects*; D012189:Retrospective Studies; D014427:Twins / Q000706:statistics & numerical data
keywords: Assisted reproductive technology; chorionicity; obstetric cholestasis; twin pregnancies