[JAMA Pediatrics] Low to moderate prenatal alcohol exposure associated with facial differences in children at ages 6 to 8

A study is out in JAMA Pediatrics this week looking at a small group of mothers and children both pre-birth and followed up years later to measure facial features.

Researchers found that even low to moderate levels of alcohol exposure (low: <20g per occasion and <70g per week, moderate: 20-49g per occasion, <70g per week) were associated with subtle but detectable facial changes in children. The study did not find a dose-response relationship (ie, it wasn't the case that more alcohol necessarily increased the likelihood of the the distinct facial features). First trimester exposure alone was enough to be associated with the facial changes, suggesting early pregnancy is an important window for facial development.

To put this into context, in the US, the CDC considers 1 drink as 14g of alcohol. While the guidelines are slightly different in Australia, where the study was conducted, the classification of low exposure broadly align to the CDC's guidelines on exposure levels. Some popular parenting researchers (e.g. Emily Oster) suggest that 1-2 drinks per week in the first trimester and 1 drink per day in later trimesters have not been associated with adverse outcomes. However, critics have suggested that fetal alcohol exposure has a spectrum of effects, and our classic definition of FAS may not encompass them all.

Two caveats to the research to consider:

• While fetal alcohol syndrome has distinctive facial features (which are one of the diagnostic markers) that's not what this study was looking at. Instead, this study identified subtle but significant changes among children who were exposed to low to moderate alcohol in utero including slight changes in eye shape and nose structure, and mild upper lip differences. In other words—these children didn't and don't meet diagnostic criteria for FAS
• The researchers did not observe any differences in cognitive or neurodevelopmental outcomes among the participants. They do suggest that further follow up would be useful to assess if cognitive differences present later on. It may not matter to have a very slightly different face than others if that's the only impact you experience.