title: Tocolytic therapy for preterm delivery: systematic review and network meta-analysis.
abstract: OBJECTIVE
  To determine the most effective tocolytic agent at delaying delivery.
  
  
  METHODS
  Systematic review and network meta-analysis.
  
  
  METHODS
  Cochrane Central Register of Controlled Trials, Medline, Medline In-Process, Embase, and CINAHL up to 17 February 2012.
  
  
  METHODS
  Randomised controlled trials of tocolytic therapy in women at risk of preterm delivery.
  
  
  METHODS
  At least two reviewers extracted data on study design, characteristics, number of participants, and outcomes reported (neonatal and maternal). A network meta-analysis was done using a random effects model with drug class effect. Two sensitivity analyses were carried out for the primary outcome; restricted to studies at low risk of bias and restricted to studies excluding women at high risk of preterm delivery (those with multiple gestation and ruptured membranes).
  
  
  RESULTS
  Of the 3263 titles initially identified, 95 randomized controlled trials of tocolytic therapy were reviewed. Compared with placebo, the probability of delivery being delayed by 48 hours was highest with prostaglandin inhibitors (odds ratio 5.39, 95% credible interval 2.14 to 12.34) followed by magnesium sulfate (2.76, 1.58 to 4.94), calcium channel blockers (2.71, 1.17 to 5.91), beta mimetics (2.41, 1.27 to 4.55), and the oxytocin receptor blocker atosiban (2.02, 1.10 to 3.80). No class of tocolytic was significantly superior to placebo in reducing neonatal respiratory distress syndrome. Compared with placebo, side effects requiring a change of medication were significantly higher for beta mimetics (22.68, 7.51 to 73.67), magnesium sulfate (8.15, 2.47 to 27.70), and calcium channel blockers (3.80, 1.02 to 16.92). Prostaglandin inhibitors and calcium channel blockers were the tocolytics with the best probability of being ranked in the top three medication classes for the outcomes of 48 hour delay in delivery, respiratory distress syndrome, neonatal mortality, and maternal side effects (all cause).
  
  
  CONCLUSIONS
  Prostaglandin inhibitors and calcium channel blockers had the highest probability of delaying delivery and improving neonatal and maternal outcomes.
authors.affiliation: Department of Obstetrics and Gynecology, Indiana University School of Medicine, Indianapolis, IN, USA. dahaas@iupui.edu
authors.forename: David M
authors.initials: DM
authors.lastname: Haas
authors.forename: Deborah M
authors.initials: DM
authors.lastname: Caldwell
authors.forename: Page
authors.initials: P
authors.lastname: Kirkpatrick
authors.forename: Jennifer J
authors.initials: JJ
authors.lastname: McIntosh
authors.forename: Nicky J
authors.initials: NJ
authors.lastname: Welton
mesh_terms: D002121:Calcium Channel Blockers / Q000627:therapeutic use; D005260:Female; D006801:Humans; D008278:Magnesium Sulfate / Q000627:therapeutic use; D007752:Obstetric Labor, Premature / Q000517:prevention & control*; D011247:Pregnancy; D011248:Pregnancy Complications / Q000517:prevention & control; D011256:Pregnancy Outcome; D011448:Prostaglandin Antagonists / Q000627:therapeutic use; D016032:Randomized Controlled Trials as Topic; D013997:Time Factors; D015145:Tocolysis / Q000379:methods*; D015149:Tocolytic Agents / Q000627:therapeutic use*; D016896:Treatment Outcome; D014668:Vasotocin / Q000031:analogs & derivatives / Q000627:therapeutic use
chemical_list: D002121:Calcium Channel Blockers; D011448:Prostaglandin Antagonists; D015149:Tocolytic Agents; C047046:atosiban; D008278:Magnesium Sulfate; D014668:Vasotocin