Canadian researchers find no link between mothers using pain-relieving drugs and rates of hospital admission or death among infants.
Infants breastfed by mothers taking opioids shortly after delivery are at no greater risk of adverse outcomes, a new Canadian study has shown.
Using data from more than 170,000 mother and infant pairs, researchers found no association between postpartum opioid prescription and infant hospital admission or death.
“Although we endorse caution in short-term postpartum opioid use in selected mothers, clinicians and parents should be reassured that infants are at low risk of harm,” they wrote in the BMJ.
The case-controlled study followed 86,000 mothers prescribed opioids in the week after delivery, matched with a similar number of controls over an eight-year period, and found the percentage of infants admitted to hospital was the same for those whose mothers were prescribed opioids and those who weren’t. In the 30 days following delivery, 3.5% of infants were admitted to hospital, regardless of whether their mothers filled an opioid prescription.
Researchers also found that 80% of the mothers prescribed opioids had delivered by caesarean section, compared to 21% of those in the control group.
Although the risk of emergency room visits (as opposed to admissions) rose slightly, from 10.2% to 10.6%, in infants whose mothers were prescribed opioids, there were no significant differences between the two groups for any other adverse events measured.
Oxycodone was the most frequently prescribed opioid, representing 42% of prescriptions, while 20% were for morphine and codeine and 12% for hydromorphone. For all opioids, the average length of supply was three days.
There were significant changes in the types of opioids prescribed to new mothers over the eight-year study period, the authors noted, with the number of prescriptions for codeine decreasing, while morphine and hydromorphone scripts became more common.
The finding that no serious harms were seen in infants of mothers taking opioids while breastfeeding was reassuring, the study’s authors said, given that in the past concerns had been raised about this issue.
“Concerns about opioid toxicity in breastfed infants seem to be unsubstantiated. Most of the postulated risks are based on poorly documented historical reports and relate specifically to maternal codeine use,” the researchers concluded.
