title: Epidural analgesia lengthens the Friedman active phase of labor.
abstract: OBJECTIVE
  To estimate the effect of epidural analgesia on the Friedman labor curve.
  
  
  METHODS
  This study was a secondary analysis of a previously reported randomized trial of the effects of patient-controlled epidural analgesia during labor compared with patient-controlled meperidine on cesarean delivery rate. All subjects had a singleton, cephalic, nonanomalous fetus at or beyond 37 weeks' gestation. This secondary analysis was limited to women who had cervical dilatation commencing of at least 3 cm (ie, active phase of labor).
  
  
  RESULTS
  A total of 459 women were randomized. Twenty-five women were excluded for a cervix less than 3 cm dilated, leaving 220 women allocated to patient-controlled epidural analgesia and 214 to patient-controlled intravenous meperidine available for analysis. There were no significant demographic differences between the two groups, including age, race, gestational age, and cervix on admission. The active phase of labor was 1 hour longer in the epidural-treated group (6.0 +/- 3.2 hours versus 5.0 +/- 3.2 hours, P <.001). The rate of cervical dilation was significantly less with epidural analgesia (1.4 cm/h versus 1.6 cm/h, P <.002). The duration of the second stage tended to be longer in the epidural group (1.1 +/- 1.5 hours versus 0.9 +/- 1.0 hours, P =.079).
  
  
  CONCLUSIONS
  Epidural analgesia prolonged the active phase of labor by 1 hour compared with Friedman's original criteria.
authors.affiliation: Department of Obstetrics and Gynecology, The University of Texas Southwestern Medical Center at Dallas, 75390-9032, USA. james.alexander@utsouthwestern.edu
authors.forename: James M
authors.initials: JM
authors.lastname: Alexander
authors.forename: Shiv K
authors.initials: SK
authors.lastname: Sharma
authors.forename: Donald D
authors.initials: DD
authors.lastname: McIntire
authors.forename: Kenneth J
authors.initials: KJ
authors.lastname: Leveno
mesh_terms: D000293:Adolescent; D000328:Adult; D015360:Analgesia, Epidural / Q000379:methods*; D016362:Analgesia, Obstetrical / Q000379:methods*; D016058:Analgesia, Patient-Controlled / Q000379:methods*; D020070:Cervical Ripening / Q000187:drug effects; D002585:Cesarean Section; D005260:Female; D006801:Humans; D007262:Infusions, Intravenous; D007749:Labor Stage, Third / Q000187:drug effects* / Q000502:physiology; D008614:Meperidine / Q000008:administration & dosage*; D010147:Pain Measurement; D011247:Pregnancy; D011256:Pregnancy Outcome; D011336:Probability; D012016:Reference Values; D016896:Treatment Outcome
chemical_list: D008614:Meperidine