Postpartum maternal opioid treatment is not associated with adverse infant outcomes

Infants born to mothers who were prescribed opioids after birth, primarily after a caesarean section, are not at greater risk of early harm than infants born to mothers who were not prescribed opioids, according to the BMJ today. It was revealed in a large-scale study from Canada that was published.

These findings should reassure clinicians and parents that these infants are at low risk of harm, the researchers said.

Opioids such as codeine and morphine are often given to patients to relieve pain immediately after surgery. All opioids pass into breast milk, although in amounts that are not expected to harm a breastfed infant, but concerns that opioids in breast milk may pose risks remain controversial. There is

To address this uncertainty, Canadian researchers set out to investigate whether postnatal maternal opioid treatment is associated with an increased risk of adverse outcomes in infants.

They used 8-year medical data from 865,691 mother-infant pairs who were discharged from hospitals in Ontario within 7 days of delivery between September 1, 2012, and March 31, 2020.

After the exclusion was applied, 85,852 mothers filled out an opioid prescription within 7 days of discharge, and 538,815 mothers did not. Each mother who prescribed opioids within 7 days of hospital discharge was matched with mothers who did not (control group).

Most of the mothers in the matched cohort (81%) delivered by caesarean section. Of the mothers prescribed opioids, 42% received oxycodone, 20% codeine, 19% morphine, and 12% hydromorphone for an average of 3 days.

Researchers then followed all infants for 30 days to examine a range of critical outcomes, including readmission, emergency room visits, admission to the neonatal intensive care unit, and death from any cause.

After accounting for other potentially influencing factors, such as maternal age and medical history, the researchers found that 2,962 (3.5%) of the infants hospitalized within 30 days were born to opioid-filled mothers. (3,038 (3.5%)). %) Born to a mother who is not.

Infants of mothers prescribed opioids were no more likely to be hospitalized for any reason than infants of mothers not prescribed opioids (absolute risk increase 0.08%).

Infants of mothers prescribed opioids were slightly more likely to be admitted to the emergency department in the next 30 days (absolute risk increase of 0.41%), but were more likely to experience other serious infant complications, such as respiratory distress and hospitalization. No difference in outcome was seen. He was transferred to the neonatal intensive care unit and no infant deaths occurred.

As this was an observational study, we were unable to determine the cause, and the researchers found several factors, including how much medication was taken, the use of other over-the-counter pain relievers, and the lack of information about breastfeeding status. In addition, we cannot exclude the possibility that other unmeasured factors may have influenced the results.

Nonetheless, they note that Canada has a very high early breastfeeding rate (90%), giving them a great deal of confidence in their conclusions. Consistent with the fact that mothers are prescribed opioids after delivery, no convincing reports of severe opioid toxicity in infants associated with breastfeeding have been published.

As such, they conclude:

This new study shows that opioids do not present unique risks to infants of nursing mothers, said an expert in the linked editorial.

Alternative pain relievers, including nonsteroidal anti-inflammatory drugs, are also generally harmless to babies, they add, but short-acting pain relievers are recommended for nursing mothers.

However, they point out that the evidence for optimal postnatal pain relief, especially for breastfeeding mothers, is scarce, and that the balance of risks and benefits for both mother and baby remains uncertain. need more research, they say.