title: Isolated Oligohydramnios at Term as an Indication for Labor Induction: A Systematic Review and Meta-Analysis.
abstract: OBJECTIVE
  To investigate whether isolated oligohydramnios at term is associated with increased rates of perinatal morbidity and mortality and whether induction of labor in term pregnancies with isolated oligohydramnios is superior to conservative management in reducing perinatal morbidity and mortality.
  
  
  METHODS
  We searched databases from inception to May 2015. We included studies that evaluated isolated oligohydramnios at term and perinatal outcome. Each outcome was analyzed separately, performing a comparative analysis between the study and control groups.
  
  
  RESULTS
  Twelve studies were included with 35,999 women: 2,414 (6.7%) with isolated oligohydramnios and 33,585 (93.29%) with normal amniotic fluid index. Patients with isolated oligohydramnios had significantly higher rates of labor induction [odds ratio (OR) 7.56, confidence interval (CI) 4.58-12.48] and Cesarean sections (OR 2.07, CI 1.77-2.41). There were higher rates of an Apgar score <7 at 1 and 5 min (OR 1.53, CI 1.03-2.26, and OR 2.01, CI 1.3-3.09, respectively) and admission to the neonatal intensive care unit (OR 1.47, CI 1.17-1.84). There were no significant differences in cord pH <7.1 and meconium-stained amniotic fluid. In the single randomized trial comparing induction of labor with expectant management, no differences were found in any significant maternal or neonatal outcomes.
  
  
  CONCLUSIONS
  Isolated oligohydramnios at term is associated with significantly higher rates of labor induction, Cesarean sections, and short-term neonatal morbidity.
authors.affiliation: Department of Obstetrics and Gynecology, Hillel Yaffe Medical Center, Hadera, Israel.
authors.forename: Guy
authors.initials: G
authors.lastname: Shrem
authors.forename: Sima S
authors.initials: SS
authors.lastname: Nagawkar
authors.forename: Mordechai
authors.initials: M
authors.lastname: Hallak
authors.forename: Asnat
authors.initials: A
authors.lastname: Walfisch
mesh_terms: D000328:Adult; D000653:Amniotic Fluid; D002585:Cesarean Section; D036861:Delivery, Obstetric; D005260:Female; D006801:Humans; D007751:Labor, Induced; D016017:Odds Ratio; D016104:Oligohydramnios / Q000000981:diagnostic imaging* / Q000401:mortality; D011247:Pregnancy; D011256:Pregnancy Outcome; D011263:Pregnancy Trimester, Third; D047929:Term Birth