WEDNESDAY, Feb. 16, 2005 (HealthDay News) -- In news that's sure to bring a big sigh of pain relief to pregnant women, a new study has found that epidurals given early in labor don't increase the odds of Cesarean birth.
The study, published in the Feb. 17 issue of the New England Journal of Medicine, also exonerated early epidurals as a cause of longer labor when compared to epidurals given later in labor.
And, not surprisingly, the study also found that epidural anesthesia provided more complete pain relief than opioid medications.
"If a woman wants to have an epidural, there's no reason she shouldn't ask for it and get it when she needs it," said study author Dr. Cynthia Wong, an associate professor of anesthesiology at Northwestern University Feinberg School of Medicine in Chicago.
An epidural is an injection of anesthesia into the area that surrounds the spinal cord in the lower back. After an epidural, the abdomen, pelvis and genital areas are anesthetized, the researchers said.
Traditionally, women in labor have been told they have to wait until their cervix is dilated 4 or 5 centimeters before they can receive an epidural. That's because past research had shown an association between epidurals and C-sections.
However, Wong and others suspected that epidurals weren't to blame. It may simply have been that women who requested early pain relief had other risk factors for C-section delivery. For example, said Wong, a baby with a large head circumference increases the risk of Cesarean birth and also may cause more pain than a baby with a smaller head, prompting the mother to ask for earlier pain relief.
To test this theory, Wong and her colleagues conducted a randomized trial that included 750 healthy, first-time mothers. Half of the group received an epidural at their first request for pain relief, while the other half received an opioid analgesic, such as a morphine-like drug.
Women in the opioid group were assessed at their second request for pain relief. If they were less than 4 centimeters dilated, they were given another dose of opioid analgesia. If they were dilated more than 5 centimeters, they were given an epidural. After the third request for pain relief, they were given an epidural regardless of their dilation status.
The researchers confirmed what they had suspected -- early epidurals didn't increase the rate of Cesarean births. In fact, the early epidural group had an 18 percent C-section rate, while the opioid group had a 21 percent rate.
The average time between the administration of any pain relief to complete dilation was 295 minutes for women receiving early epidurals compared to 385 minutes for the opioid group. Overall length of labor was shorter for the early epidural group as well -- 398 minutes versus 479 minutes for the opioid group.
Babies born to mothers given an opioid analgesic were significantly more likely to have a one-minute Apgar score of less than seven -- 24 percent versus 16.7 percent for the early epidural group, according to the study. Apgar tests are given at one minute and five minutes after birth to determine the overall condition of a newborn.
"We found that the C-section rate did not differ, and we also found that women with early epidurals had much better pain relief, labors went faster by over 80 minutes and their babies were born with higher Apgar scores," said Wong.
Dr. Gilbert Grant, an obstetrical anesthesiologist at New York University Medical Center, said, "This article validates what we've been saying in obstetrical anesthesia."
"There is no reason to wait until some arbitrary degree of cervical dilation occurs before receiving epidural pain relief," Grant added. "Labor without an epidural hurts. Modern medicine allows you to enjoy your labor without pain. Getting an early epidural is totally reasonable and should not be expected to cause any deleterious effects on the course and outcome of labor."
Grant said pregnant women should discuss the issue of pain relief with their doctor or midwife long before labor begins. He said it's also a good idea for women to contact the hospital and talk with the anesthesiologist to make sure they're going to get the pain relief they want.
Wong noted that her study didn't look at whether epidurals versus no pain relief led to prolonged labor, and added that such a study would be nearly impossible to randomize.
But Grant said, given that women who had early epidurals had shorter labor in this study, that probably wouldn't be the case.
More information
Learn more about epidurals at the American Pregnancy Association.
