The interrelationship between vaginal labor, cytokine production, and epidural analgesia is unknown. Vaginal delivery is thought to induce a maternal inflammatory response. Though epidural analgesia during labor was found to significantly influence peripartum maternal and newborn interleukin concentrations, these studies did not address at what stage epidural analgesia was performed. Preemptive analgesia has been found to be associated with attenuated proinflammatory cytokines, at least in the postoperative period.