Some stressed-out expectant women might ask, what’s the harm in a small glass of wine? Plenty, according to new research showing that even modest consumption of alcohol can damage the developing fetal brain.

Pediatric researchers studied mother-newborn pairs from the United States and South Africa and discovered that babies born to mothers who reported drinking small amounts of alcohol demonstrated increased brain activity in an area of the brain associated with developmental issues later in life. The median amount of alcohol consumed during each trimester was five drinks, and the resulting brain activity was also found to occur among neonates whose mothers only drank a small amount during the first trimester.

A similar effect was observed in infants whose mothers smoked a low number of cigarettes during their pregnancy or quit smoking after the first trimester.

Newborns whose mothers quit smoking after the first trimester or smoked a low number of cigarettes during their pregnancy also had brain activity that suggests future developmental issues.

Researchers have long documented the numerous negative long-term effects of excessive alcohol and tobacco exposure on fetal development. For example, fetal alcohol syndrome, a well-known symptom of significant alcohol consumption during pregnancy, can cause brain damage and growth problems.

Pregnancy can be a stressful time for women, but before reaching for a glass of alcohol, consider healthier outlets such as meditation or talking with a loved one. Sometimes, comfort can be the best medicine.