title: The effect of chorionicity and twin-to-twin delivery time interval on short-term outcome of the second twin.
abstract: OBJECTIVE
  To investigate the effect of chorionicity and twin-to-twin delivery time interval on short-term outcome in the second twin as well as to investigate the predictors of adverse outcome in both twins.
  
  
  METHODS
  Data included vaginally delivered twins (≥36 weeks) from Copenhagen University Hospitals (2001-2009). The association between delivery interval and adverse outcome parameters was compared for monochorionic (MC) and dichorionic (DC) twins by multiple linear regression. Predictors were studied by logistic regression.
  
  
  RESULTS
  There were 554 twin pairs, of which 57 were MC and 485 DC. We found no difference in the decrease of pH (p = 0.912) and Apgar (p = 0.609) in relation to increasing time interval. Neonatal unit (NICU) admissions did not differ (p = 0.167). Apgar ≤7 (p < 0.001) and pH ≤ 7.20 (p = 0.002) increased first twin risk of NICU admission, whereas first (p = 0.001) or second (p < 0.001) twin Apgar ≤7 and second twin pH ≤7.00 (p = 0.003) increased second twin risk of NICU admission.
  
  
  CONCLUSIONS
  Increasing delivery interval was associated with a significant decrease in pH and Apgar, but there was no difference between MC and DC twins. Low Apgar of the first twin increased the risk of second twin NICU admission.
authors: Department of Obstetrics and Gynecology, Roskilde Hospital , Roskilde , Denmark .
authors: Sofie
authors: S
authors: Hjortø
authors: Carsten
authors: C
authors: Nickelsen
authors: Janne
authors: J
authors: Petersen
authors: Niels Jørgen
authors: NJ
authors: Secher
mesh_terms: D001034:Apgar Score; D001238:Asphyxia Neonatorum / Q000453:epidemiology; D001724:Birth Weight; D001946:Breech Presentation / Q000453:epidemiology; D002823:Chorion / Q000502:physiology*; D036861:Delivery, Obstetric; D005260:Female; D005312:Fetal Blood / Q000737:chemistry; D005865:Gestational Age; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007231:Infant, Newborn; D007363:Intensive Care Units, Neonatal; D016014:Linear Models; D010343:Patient Admission / Q000706:statistics & numerical data; D011247:Pregnancy; D012307:Risk Factors; D013997:Time Factors; D014429:Twins, Dizygotic; D014430:Twins, Monozygotic; D014469:Umbilical Arteries / Q000737:chemistry; D014620:Vacuum Extraction, Obstetrical / Q000706:statistics & numerical data