title: Perinatal complications associated with preterm deliveries at 24 to 33 weeks and 6 days gestation (2011- 2012): A hospital-based retrospective study.
abstract: BACKGROUND
  Morbidity and mortality of preterm babies are important issues in perinatal medicine. In developed countries, preterm delivery is the cause of about 70% of mortality and 75% of morbidity in the neonatal period, respectively.
  
  
  OBJECTIVE
  The aim of this study was to determine the risk factors for preterm labor and the outcomes, in terms of perinatal mortality and morbidity at the time of discharge home, among preterm infants at less than 34 weeks gestation.
  
  
  METHODS
  A retrospective study was conducted and all infants with a gestational age of 24 to 33 weeks and 6 days who were born from November 1(st), 2011 to March 31, 2012 were enrolled in this study.
  
  
  RESULTS
  From 1185 preterm infants were born during this period, 475 (40.08%) infants with less than 34 weeks gestational age were included in the study. Our study showed the major obstetrical risk factors for preterm labor were as follows: preeclampsia (21%), premature rupture of membranes (20.3%), abruption of placenta (10%), and idiopathic cases (48.7%). The neonatal mortality rate in less than 34 weeks was 9.05%. Significant perinatal morbidity causesd in less than 34 weeks were as follows: sepsis (46.94%), respiratory distress syndrome (41.47%), patent ductus arteriosus (21.47%), retinopathy of prematurity (3.57%), necrotizing entrocolitis (1.68%), intra-ventricular hemorrhage (9%), and broncho-pulmonary dysplasia (0.84%).
  
  
  CONCLUSIONS
  Preterm birth is associated with adverse perinatal outcome. This situation needs to be improved by directing appropriately increased resources for improving prenatal health services and providing advanced neonatal care.
authors.affiliation: Neonatal Unit, Mahdiyeh Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Maryam
authors.initials: M
authors.lastname: Khoshnood Shariati
authors.affiliation: Feto-Maternal Unit, Mahdiyeh Hospital, Tehran, Iran.
authors.forename: Zohreh
authors.initials: Z
authors.lastname: Karimi
authors.affiliation: Department of Obstetrics and Gynecology, Mahdiyeh Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Mahroo
authors.initials: M
authors.lastname: Rezaienejad
authors.affiliation: Neonatal Unit, Mahdiyeh Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Azita
authors.initials: A
authors.lastname: Basiri
authors.affiliation: Department of Obstetrics and Gynecology, Mahdiyeh Hospital, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Farahnaze
authors.initials: F
authors.lastname: Torkestani
authors.affiliation: Infertility and Reproductive Health Research Center, Shahid Beheshti University of Medical Sciences, Tehran, Iran.
authors.forename: Soraya
authors.initials: S
authors.lastname: Saleh Gargari
keywords: Infant death; Necrotizing entrocolitis; Pre-eclampsia; Premature rupture of fetal membranes; Respiratory distress syndrome