• neonatal death
  
• early onset neonatal sepsis
  

• maternal and umbilical cord plasma N-acetylcysteine levels
  
• maternal and umbilical cord plasma antioxidant capacity
  
• maternal and umbilical cord blood glutathione concentration
  
• umbilical cord levels of inflammatory cytokine concentrations
  
• funisitis grades
  
• other neonatal outcomes (respiratory distress syndrome, necrotizing enterocolitis, intraventricular hemorrhage, retinopathy of prematurity, late-onset sepsis, bronchopulmonary dysplasia)
  

Despite extensive research, the etiology of most preterm births remains unknown. There are significant fetal consequences associated with preterm birth, which include necrotizing enterocolitis, fetal respiratory distress and intra-ventricular hemorrhage. Perinatal mortality is about 44%, 11% and 5% when deliveries occur between 25-28 weeks, 29-32 weeks and 33-34 weeks, respectively. While for many years, it was assumed that the cause of the high morbidity associated with prematurity was the birth of a neonate with a restricted adaptive capacity, it has also been suggested that part of the high perinatal morbidity was the consequence of adverse processes affecting the fetus in utero, rather than of prematurity per se. Intra-amniotic inflammation present in utero early in gestation may trigger the cascade of events leading to preterm birth (i.e. rupture of membranes, cervical ripening, uterine contractions) and provide an intrauterine milieu which is unfavorable or even harmful to the fetus.

Most living organisms have developed well-integrated, antioxidant defenses to scavenge free radicals and control their intracellular concentration. A loss of balance between free radicals and antioxidants (the redox balance) is one mechanism of cell injury in diseases associated with inflammation. N-acetylcysteine is an approved anti-oxidant medication drug used during pregnancy for treatment of mothers with acetaminophen (Tylenol) toxicity. N-acetylcysteine has been safely administered during pregnancy in over 100 women who overdosed with Tylenol and to preterm and healthy term newborns for other purposes. It is a goal of our trial to prevent free radical formation by administering N-acetylcysteine and to further study whether the outcome of preterm deliveries will improve.