title: Effect of parity on maternal and neonatal outcomes in twin gestations.
abstract: OBJECTIVE
  To compare maternal and neonatal outcomes of twin gestations in nulliparous and multiparous women.
  
  
  METHODS
  Retrospective analysis of maternal and neonatal records.
  
  
  METHODS
  American University of Beirut Medical Center, a referral university-affiliated hospital.
  
  
  METHODS
  Pregnant women who delivered twin gestations beyond 24 weeks from 1990 to 2004.
  
  
  METHODS
  The data collected were analyzed using Student's paired t-test or χ(2) test. Logistic regression analysis was used to study the effect of multiple variables on preterm delivery.
  
  
  METHODS
  Preterm birth rate.
  
  
  RESULTS
  Nulliparas (n=333) were more likely to be younger (28.1±5.4 vs. 30.0±5.2 years; p<0.001) and the pregnancy a product of assisted reproductive technology (23.1 vs. 4.5%; p<0.001) compared with multiparas (n=508). They were at significantly increased risk of preterm delivery (54.4 vs. 45.1%; p=0.009) at lower gestational age (35.6±3.2 vs. 36.2±3.0 weeks; p=0.004). They had longer first and second stages of labor and a higher cesarean delivery rate (61.3 vs. 44.9%; p<0.001). Except for a higher intensive care nursery admission rate and longer nursery stay for twins of nulliparas, all neonatal morbidities were comparable. On multiple logistic regression analysis, multiparity (relative risk 0.70, 95% confidence interval 0.51-0.97) and growth restriction (relative risk 0.16, 95% confidence interval 0.12-0.22) were protective, while discordance (relative risk 2.24, 95% confidence interval 1.40-3.60) was a predictor of preterm delivery.
  
  
  CONCLUSIONS
  Nulliparous women with twin gestations are at significantly higher risk for preterm delivery and cesarean delivery compared with multiparous women. Although this was not translated into higher perinatal mortality, these women should be monitored closely and counseled regarding these risks and their attendant morbidity.
authors: Department of Obstetrics and Gynecology, American University of Beirut Medical Center, Beirut, Lebanon.
authors: Antoine
authors: A
authors: Hannoun
authors: Department of Obstetrics and Gynecology, American University of Beirut Medical Center, Beirut, Lebanon.
authors: Ihab M
authors: IM
authors: Usta
authors: Department of Obstetrics and Gynecology, American University of Beirut Medical Center, Beirut, Lebanon.
authors: Johnny
authors: J
authors: Awwad
authors: Department of Obstetrics and Gynecology, Eastern Virginia Medical School, Norfolk, VA, USA.
authors: Darine
authors: D
authors: Moukalled
authors: Department of Obstetrics and Gynecology, Riverside Regional Medical Center, Newport News, VA, USA.
authors: Fadi
authors: F
authors: Yahya
authors: Department of Obstetrics and Gynecology, American University of Beirut Medical Center, Beirut, Lebanon.
authors: Amin
authors: A
authors: Jurdi
authors: Department of Obstetrics and Gynecology, American University of Beirut Medical Center, Beirut, Lebanon.
authors: Anwar H
authors: AH
authors: Nassar
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