Study: Drinking while breastfeeding linked with children’s reasoning deficits

Children exposed to alcohol in breastmilk didn’t perform as well as other children on reasoning tests at ages 6 and 7, according to a new study.

Researchers did not find a link between maternal smoking and children’s test scores.

The Academy recommends breastfeeding mothers limit their alcohol intake and refrain from drinking two hours or less before breastfeeding as the alcohol could impact their infant’s motor development. It also discourages smoking as it is linked to sudden infant death syndrome and increased allergy incidence. Both also impact milk production.

Researchers set out to see if there are ties between breastfeeding mothers’ alcohol or nicotine use and children’s cognitive development. They used data on 5,107 infants from Growing Up in Australia: The Longitudinal Study of Australian Children that followed up with participants every two years. Mothers were asked about their alcohol and tobacco use, while children’s cognition was measured with vocabulary, reasoning and literacy/numeracy tests.

Children’s reasoning test scores at age 6-7 were lower if their mothers drank alcohol while breastfeeding, and the scores were lowest for those whose mothers drank the most. The association held up while controlling for numerous factors, including prenatal alcohol consumption, sex, income and birthweight. However, the association was small and “clinical implications may be limited unless mothers drink large quantities, or frequently binge drink,” authors said in the report “Drinking or Smoking While Breastfeeding and Later Cognition in Children” (Gibson L, Porter M. Pediatrics. July 30, 2018, https://doi.org/10.1542/peds.2017-4266).

There was no link between a mother’s drinking and her child’s reasoning scores if she did not breastfeed.

“This suggest that alcohol exposure through breastmilk was responsible for cognitive reductions in breastfed babies, rather than psychosocial or environmental factors surrounding maternal alcohol consumption,” authors wrote.

They said brain development may have been impacted by the ethanol or by changes in feeding and sleeping patterns that came with alcohol consumption. However, test scores did not seem to be impacted as the children got older. There also was no association between a mother’s tobacco use and her child’s test scores.

The author of a related commentary noted the findings are consistent with animal models.

“Previous recommendations that find limited alcohol consumption compatible with breastfeeding during critical periods of development, such as the first months of life may need to be reconsidered in light of this combined evidence,” she wrote.