title: A prospective, randomized, controlled trial of high and low maintenance doses of magnesium sulfate for acute tocolysis.
abstract: OBJECTIVE
  This study was undertaken to compare a high-dose protocol for magnesium sulfate tocolytic therapy with a low-dose regimen with respect to time needed to achieve tocolysis.
  
  
  METHODS
  Patients between 24 and 34 weeks' gestation with preterm labor were included. Patients with ruptured membranes or nonreassuring fetal assessments were excluded. Gravid women received a 4-g loading dose of magnesium sulfate and were prospectively randomly assigned to receive a maintenance dose of 2 or 5 g/h.
  
  
  RESULTS
  The median times to tocolysis were 120 minutes (semi-interquartile range, 30 minutes) in the low-dose group and 90 minutes (semi-interquartile range, 28 minutes) in the high-dose group (P <.001).
  
  
  CONCLUSIONS
  Patients treated with a higher maintenance dose of magnesium sulfate had a higher frequency of side effects; however, tocolysis was achieved more rapidly and they required shorter admissions to the labor and delivery unit without increased maternal or neonatal morbidity.
authors.affiliation: Department of Obstetrics and Gynecology, University of Mississippi Medical Center, , Jackson, USA.
authors.forename: D A
authors.initials: DA
authors.lastname: Terrone
authors.forename: B K
authors.initials: BK
authors.lastname: Rinehart
authors.forename: E S
authors.initials: ES
authors.lastname: Kimmel
authors.forename: W L
authors.initials: WL
authors.lastname: May
authors.forename: J E
authors.initials: JE
authors.lastname: Larmon
authors.forename: J C
authors.initials: JC
authors.lastname: Morrison
mesh_terms: D000328:Adult; D004305:Dose-Response Relationship, Drug; D005260:Female; D006801:Humans; D008278:Magnesium Sulfate / Q000008:administration & dosage* / Q000009:adverse effects / Q000627:therapeutic use; D011247:Pregnancy; D011446:Prospective Studies; D013997:Time Factors; D015145:Tocolysis / Q000009:adverse effects / Q000379:methods*; D015149:Tocolytic Agents / Q000008:administration & dosage* / Q000627:therapeutic use
chemical_list: D015149:Tocolytic Agents; D008278:Magnesium Sulfate