Early epidurals do not increase risk of Cesarean delivery

A study published in this week's New England Journal of Medicine by researchers at Northwestern Memorial Hospital refutes the popular belief that getting an epidural early in labor increases a woman's risk of cesarean delivery.

In a study of 750 women, researchers found that getting an epidural when the cervix is less than four centimeters dilated did not increase the cesarean delivery rate and provided significantly better pain relief. "We also found shorter labors in the early epidural group compared to those who received the standard narcotic – an injection of hydromorphone (a morphine-like drug) – and didn't get the epidural until after four centimeters dilation," says lead author Cynthia Wong, MD, section chief for Obstetric Anesthesiology at Northwestern Memorial Hospital and associate professor of Anesthesiology at Northwestern University's Feinberg School of Medicine. "In addition, the babies whose mothers had early epidurals had a decreased incidence of having a below normal one-minute Apgar score." Apgar scores are a widely used assessment of a newborn's initial condition that factors heart rate, respiration, muscle tone, reflux response and color.

The American College of Obstetricians and Gynecologists recommends that when feasible, obstetric practitioners should delay the administration of epidural anesthesia in women with their first pregnancy until the cervical dilation reaches at least 4 to 5 centimeters and other forms of analgesia should be used until that time. This recommendation was based on studies that found an association between the initiation of epidurals early in labor and an increased cesarean delivery rate. "We hypothesized that the findings of these earlier studies linking epidurals to increased risk of cesarean delivery could be explained by other factors," says Dr. Wong. "For example, asking for an epidural earlier may be a marker for a bigger baby, which causes more pain early in labor and also increases the risk for a cesarean delivery."

Dr. Wong's study randomized 750 women in labor with cervical dilation less than four centimeters into two groups: the early epidural group (women who received spinal-epidural pain relief at the first request for pain relief); and the post four centimeter group (women who received a shot of hydromorphone at the first pain-relief request and then received an epidural at four centimeters dilation or greater or at the third pain relief request).

"Women often feel guilty or weak when they request an epidural early in labor. I hope this study will help women see that there is no shame in asking for an epidural," says Dr. Wong. "The message for women and their obstetricians and gynecologists is that there is no reason why women who want an epidural should not get it when they first request it."

"As obstetricians, we have found epidurals to provide the best pain relief during labor," adds Alan Peaceman, MD, chief of the Division of Maternal Fetal Medicine at Northwestern Memorial Hospital, and a co-author of the study. "As a result of this research, I now feel more comfortable offering an epidural to a patient earlier in labor without concern for it adversely impacting the course of labor. The techniques used in administering the epidural medications have evolved over the last two decades, and this may explain the difference from older studies showing a slowing of labor and more cesarean deliveries."