Epidural analgesia and fetal head malposition at vaginal delivery

Obstet Gynecol. 2001 Apr;97(4):608-12. doi: 10.1016/s0029-7844(00)01230-8.


Objective: To determine if nulliparas who delivered with on-demand epidural analgesia are more likely to have malpositioning of the fetal vertex at delivery than women delivered during a period of restricted epidural use.

Methods: A retrospective cohort of nulliparous women with spontaneous labor delivered during a 12-month period immediately before the availability of on-demand labor epidural analgesia was compared with a similar group of nulliparas delivered after labor epidural analgesia was available on request. The primary outcome variable was a non-occiput anterior position or malpositioned fetal head at vaginal delivery.

Results: The frequency of epidural use increased from 0.9% before epidural analgesia became available on demand to 82.9% afterward. Fetal head malpositioning at vaginal delivery occurred in 26 of 434 (6.0%) women delivered in the before period compared with 29 of 511 (5.7%) in the after period (relative risk 0.95, 95% confidence interval 0.6, 1.6). No statistically significant difference in the incidence of fetal head malpositioning was present after patients were stratified by mode of delivery (Mantel-Haenszel weighted relative risk 0.94, 95% confidence interval 0.6, 1.4). The study sample size provided 85% power to detect a two-fold increase in the incidence of fetal malpositioning from a baseline rate of 6% associated with on-demand epidural use.

Conclusion: Providing on-request labor epidural analgesia to nulliparas in spontaneous labor did not result in a clinically significant increase in the frequency of fetal head malpositioning at vaginal delivery.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Analgesia, Epidural / adverse effects*
  • Cohort Studies
  • Delivery, Obstetric*
  • Female
  • Humans
  • Labor Presentation*
  • Obstetric Labor Complications / etiology*
  • Parity
  • Pregnancy
  • Retrospective Studies