NEW YORK (Reuters Health) - Some women who get epidural anesthesia during childbirth may have difficulty with breastfeeding in the short- and long-term, a new study suggests.

Specifically, researchers found, women who received an epidural with the narcotic fentanyl seemed to have more problems with breastfeeding than women who went without an epidural.

They reported more difficulty with breastfeeding in the first week of their babies' lives, and they were twice as likely to have given up breastfeeding by the time the baby was 6 months old.

Though it's not clear that the epidurals were the reason, there is evidence from other research that fentanyl can hinder infants' ability to suckle, Dr. Siranda Torvaldsen, the study's lead author, told Reuters Health.

There's no evidence, however, that other drugs used in epidurals interfere with breastfeeding, according to Torvaldsen, a researcher at the University of Sydney in Australia.

Moreover, the findings, which are published in the International Breastfeeding Journal, do not mean women should feel guilty about wanting an epidural.

"I think the most important message for pregnant women is to get good advice and help with breastfeeding," Torvaldsen said. Lactation consultants, she noted, can help women learn how to best support breastfeeding and overcome any difficulties they may encounter.

"For many women, the benefits of epidural analgesia will outweigh the risks and it is important that women feel supported whatever decision they make," Torvaldsen said.

Of the 1,260 women in the current study, one-third had an epidural during labor. All of the epidurals included fentanyl and an anesthetic called bupivacaine.

Overall, the study found, women who received an epidural were more likely than other mothers to be partially, rather than exclusively, breastfeeding in the week after the birth.

They were also twice as likely to report breastfeeding difficulties in the first week and to give up breastfeeding before the baby was 6 months old.

In general, experts recommend that babies be fed only breast milk for the first 6 months, and then continue breastfeeding after solid foods are introduced, for at least the first year of life.

Although it's not certain that epidural drugs directly cause problems with breastfeeding, Torvaldsen said it's important that women be aware of the possibility, so they can make "informed decisions" about analgesia, and seek advice on successful breastfeeding if they need it.