Researchers from the University of Sydney examined 1,300 women who gave birth in 1997 and found that, of the 93 percent who breastfed their babies in the first week, those who had opted for epidurals were far more likely to have breastfeeding difficulties.
While three-quarters of the women who had no analgesia (painkillers) were breastfeeding their children at 24 weeks, only 53 percent of women who had received epidurals were breastfeeding at that time.
Women who'd chosen epidurals during labor were also more likely to completely stop breastfeeding prior to six months than women who opted out of pain relief.
"There is a growing body of evidence that the fentanyl (painkiller) component of epidurals may be associated with sleepy infants and difficulty establishing breastfeeding," wrote the researchers, led by Dr. Siranda Torvaldsen.
"Whatever the underlying mechanism, it is important that women who are at higher risk of breastfeeding cessation are provided with adequate breastfeeding assistance and support, both in the initial postpartum period and the following few months," they wrote.
Pat O'Brien, spokesman for the Royal College of Obstetricians and Gynaecologists, said that while the study is "interesting" and needs further investigation, a number of factors could have influenced Torvaldsen's findings.
O'Brien said that women who choose not to have epidurals may naturally be more motivated to persist in breastfeeding their babies. "Also, a lot of those women who had epidurals also went on to have Cesarean sections which -- unless you have a lot of support -- make it difficult to breastfeed because it's harder for women to pick their babies up."
Torvaldsen's study found that of the 416 women who opted for an epidural during childbirth, 172 also chose to give birth by Cesarean section.