Drinking During Pregnancy May Change Baby’s Brain Structure (excerpt)

Healthline
By Eileen Bailey | Fact Checked by Michael Crescione
November 21, 2022

Even small amounts of alcohol can cause changes to a developing baby’s brain structure.

That’s the conclusion of a study presented today at the annual meeting of the Radiological Society of North America (RSNA).

For years now, women have heard information about how even the occasional drink while pregnant can harm their infants.

For the new study, which hasn’t been published yet in a peer-reviewed journal, researchers used MRI images to evaluate fetal brains in babies exposed to alcohol during their mother’s pregnancy.

The scientists reported that even low to moderate alcohol consumption can change the baby’s brain structure and delay brain development.

Details on the study on alcohol and babies’ brains

The most recent study looked at brain MRIs for 24 fetuses with prenatal alcohol exposure.

The mothers were between 22 and 36 weeks pregnant at the time of the MRI and the fetuses were matched 1:1 with healthy fetuses not exposed to alcohol.

The scientists determined alcohol use based on surveys completed by the mothers anonymously. Overall, 17 mothers reported drinking relatively infrequently, with an average alcohol consumption of less than one drink per week.

Other responses indicated:

• Three mothers indicated drinking one to three drinks per week
• Two mothers drank four to six weeks per week
• One mother consumed an average of 14 drinks per week
• Six mothers reported at least one binge-drinking episode

The scientists reported that in fetuses with alcohol exposure:

• The total maturation score was significantly lower
• The temporal and right superior temporal sulcus, regions of the brain involved in social cognition, audiovisual integration, and language perception and development were affected

The researchers say it isn’t clear how these brain changes will affect the babies after birth and won’t know until the children are assessed when older.

However, they do assume the changes related to cognitive and behavioral difficulties will continue into childhood.

Experts discuss alcohol use during pregnancy

“This study provides additional evidence that the ingestion of alcohol affects neural development,” said Dr. G. Thomas Ruiz, the OB/GYN lead at MemorialCare Orange Coast Medical Center in Fountain Valley, California. “The fetal MRI is just the first study to document the neural changes in utero.”

“This study strengthens our evidence to counsel pregnant women to avoid alcohol consumption during pregnancy,” Ruiz told Healthline. “We need to determine if there is a critical volume of alcohol that will create a negative impact. It is unlikely that one sip of champagne on Thanksgiving or New Year’s Eve will have the same negative effect on neural development that a daily alcoholic beverage does.”

Many medical experts say that fetal alcohol spectrum disorders (FASD) can lead to learning disabilities, behavioral problems, or speech and language delays.

This study concludes that minimal alcohol consumption during pregnancy might cause harm to the unborn child.

“I do not believe that occasional alcohol consumption is OK during pregnancy,” Dr. Jessica Auffant, an OB-GYN for Orlando Health Physician Associates in Florida, told Healthline. “Although small amounts may lead to no known consequences, small amounts can cause irreversible fetal changes that we do not know about yet. This study helps confirm this recommendation.”

How much alcohol during pregnancy is too much?

However, even among the medical community, there isn’t a universal belief that small amounts of alcohol exposure can cause problems.

A report issued in 2017Trusted Source found that “there is no evidence that fetal alcohol spectrum disorder occurs in babies born to women who drink occasionally or moderately during pregnancy.”

The researchers here also indicated that only 4% to 5% of children of women who drink heavily are born with FASD.

They concluded that “there is no well-accepted scientific evidence that low or moderate levels of alcohol consumption during pregnancy – even in the first few days or weeks after conception- cause FAS or other associated problems.”

In 2020, Dr. Howard E. LeWine, wrote in an article for Harvard Health Publishing that “Minimal alcohol use during the first trimester doesn’t appear to increase the risk for high blood pressure complications, or premature birth or low birth weights.”