title: Please exit safely: maternal and twin pair neonatal outcomes according to delivery mode when twin A is vertex.
abstract: OBJECTIVE
  To investigate maternal and infant outcomes associated with delivery mode for twins with a cephalic presenting twin.
  
  
  METHODS
  Linked birth certificate and ICD hospital discharge data were analyzed retrospectively for 5573 mothers and their respective twin pairs born live at 34-42 weeks' gestation, with twin A vertex, in Washington State from 1997-2007. Relative risks (RR) and 95% confidence intervals of adverse maternal and twin pair outcomes were calculated for vaginal delivery or cesarean during labor in comparison to cesarean without labor.
  
  
  RESULTS
  Vaginal delivery or cesarean during labor was associated with significantly elevated rates of maternal hemorrhage (RR = 2.8 [2.2,3.7]), infection (RR = 2.2 [1.5,3.3]), twin pair birth injury (RR = 2.6 [1.2,5.4]) and low 5-min Apgar scores (RR = 1.4 [1.1,1.8]) and with significantly lower rates of ventilation among preterm twin pairs only (RR = 0.8 [0.7,0.9]). The lowest rate of combined poor short-term outcomes occurred in mothers and twin pairs delivered by cesarean without labor (23%) and the highest rates occurred in those with operative vaginal or cesarean during labor (39% and 34%, respectively). Among women in labor, 35% of nulliparas achieved spontaneous vaginal delivery of both twins compared to 63% of non-nulliparas.
  
  
  CONCLUSIONS
  For nulliparous women who carry twins to term, planned cesarean may improve outcomes.
authors.affiliation: a Biology Department , Seattle University , Seattle , WA , USA and.
authors.forename: Rebecca S
authors.initials: RS
authors.lastname: Hartley
authors.affiliation: b Department of Obstetrics and Gynecology , University of Washington , Seattle , WA , USA.
authors.forename: Jane
authors.initials: J
authors.lastname: Hitti
mesh_terms: D000328:Adult; D001034:Apgar Score; D002585:Cesarean Section; D036861:Delivery, Obstetric / Q000379:methods*; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D007746:Labor Presentation; D007744:Obstetric Labor Complications / Q000209:etiology*; D017063:Outcome Assessment, Health Care; D011247:Pregnancy; D059285:Pregnancy, Twin; D012189:Retrospective Studies; D014219:Trial of Labor; D014427:Twins
keywords: Cesarean section; gestational age; parity; twin pregnancy; vaginal birth