title: Acute peripartum twin-twin transfusion syndrome: incidence, risk factors, placental characteristics and neonatal outcome.
abstract: OBJECTIVE
  The aim of this study was to examine the incidence, placental characteristics and outcome in acute peripartum twin-twin transfusion syndrome (TTTS).
  
  
  METHODS
  All consecutive cases of monochorionic (MC) twins admitted to our center were included in the study. We excluded cases with chronic TTTS or twin anemia polycythemia sequence. Acute peripartum TTTS was defined when the inter-twin hemoglobin difference at birth was >8 g/dL.
  
  
  RESULTS
  A total of 241 MC twin pregnancies were included in the study. Acute peripartum TTTS was detected in six cases (2.5%, 6/241). Vaginal delivery occurred more often in the acute peripartum TTTS group compared to the control group of uncomplicated MC pregnancies, 100% (6/6) versus 57% (135/235) (P = 0.002), respectively. Acute anemia was detected only in firstborn twins. Placental angioarchitecture in acute peripartum TTTS was similar to the placentas in the control group.
  
  
  CONCLUSIONS
  The incidence of acute peripartum TTTS is low (2.5%). Birth order and mode of delivery appear to be associated with increased risk of acute peripartum TTTS.
authors.affiliation: Division of Neonatology, Department of Pediatrics, Leiden University Medical Center, Leiden, The Netherlands.
authors.forename: Enrico
authors.initials: E
authors.lastname: Lopriore
authors.forename: Nanneke
authors.initials: N
authors.lastname: Holtkamp
authors.forename: Marieke
authors.initials: M
authors.lastname: Sueters
authors.forename: Johanna M
authors.initials: JM
authors.lastname: Middeldorp
authors.forename: Frans J
authors.initials: FJ
authors.lastname: Walther
authors.forename: Dick
authors.initials: D
authors.lastname: Oepkes
mesh_terms: D000208:Acute Disease; D000328:Adult; D005260:Female; D005330:Fetofetal Transfusion / Q000453:epidemiology / Q000473:pathology / Q000503:physiopathology*; D006801:Humans; D015994:Incidence; D007226:Infant Mortality; D007231:Infant, Newborn; D008297:Male; D009426:Netherlands / Q000453:epidemiology; D058725:Peripartum Period; D010920:Placenta / Q000473:pathology*; D011247:Pregnancy; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D012307:Risk Factors
keywords: acute peripartum; hemoglobin; monochorionic twins; twin-twin transfusion syndrome