Drinking alcohol during pregnancy changes the structure of a baby's brain

A new MRI study shows that drinking alcohol during pregnancy, even in small to moderate amounts, can change a baby's brain structure and slow brain development
.
The results will be presented
next week at the annual meeting of the Radiological Society of North America (RSNA).

"Fetal MRI is a highly specialized and safe examination that allows us to accurately account for the maturation of the fetal brain," said
Gregor Kasprian, MD, senior author of the study and associate professor of radiology at the Department of Biomedical Imaging and Image-Guided Therapy at the Medical University of Vienna, Austria.

Drinking alcohol during pregnancy exposes the fetus to a group of disorders known as fetal alcohol spectrum disorder
.
Babies born with FASD may develop learning disabilities, behavioral problems, or speech and language delays
.

"Unfortunately, many pregnant women are unaware of the effects of alcohol on the fetus during pregnancy," says
Patric Kienast, MD, a doctoral student in the Department of Biomedical Imaging and Image-Guided Therapy at the Faculty of Neuroradiology and Musculoskeletal Radiology at the Medical University of Vienna.
"Therefore, we have a responsibility not only to conduct research, but also to actively educate the public about the effects of
alcohol on the fetus.
"

For the study, researchers analyzed MRIs from 24 prenatal alcohol-exposed fetuses
.
At MRI, the gestation period of the fetus is between
22 and 36 weeks.
Alcohol exposure was determined through an anonymous survey of the mother
.
The questionnaire used the Pregnancy Risk Assessment Surveillance System (PRAMS), a surveillance program of the Centers for Disease Control and Prevention and the Department of Health, and the T-ACE Screening Tool, a measurement tool for four questions to determine the risk of alcohol use
.

In alcohol-exposed fetuses, the total fetal maturity score (fTMS) was significantly lower than that of age-matched controls, and the right superior temporal sulcus (STS) was shallower
.
STS is associated
with social cognition, audiovisual integration, and language perception.

"We found the greatest changes in the temporal brain region and STS," Dr.
Casprian said
.
"We know that this region, and the formation of STS in particular, has a great influence
on language development in childhood.
"

Even with low levels of alcohol exposure, changes occurred in the fetus's brain
.

"17 out of 24 mothers drink relatively less frequently, drinking less than one drink
per week on average," says Dr Kienast.
"Nevertheless, we were able to detect significant changes
in these fetuses through prenatal MRI.
"

Three mothers drink one to three cups a week, and two mothers drink four to six cups
a week.
An average mother drinks 14 or more drinks a week
.
Six mothers also reported at least one episode of alcohol abuse during pregnancy (more than 4 at a time).

According to the researchers, delays in fetal brain development may be related to
delays in myelination and inconspicuous gyrus in the frontal and occipital lobes.

The myelination process is essential
for the functioning of the brain and nervous system.
Myelin protects nerve cells so they can transmit information
faster.
Important developmental milestones in infants, such as turning over, crawling, and language processing, are all directly related
to myelination.

Encephalic gyrus refers to the formation
of folds in the cerebral cortex.
This folding expands the cortical surface area in the limited space in the skull, thereby improving cognitive performance
.
When the rotation is weakened, the functionality is also reduced
.

"Pregnant women should strictly avoid alcohol," Dr.
Kienast said
.
"As we have shown in our study, even small amounts of alcohol intake can lead to structural changes in brain development and delays
in brain maturation.
"

It's unclear how these structural changes will affect brain development
in these babies after birth.

"To assess this accurately, we need to wait for the fetus being examined at the time to grow a little older so we can invite them back for further testing," Dr.
Kinaster said
.
"However, we can strongly assume that the changes we found contribute to cognitive and behavioral difficulties
that may arise in childhood.
"

Co-authors are Marlene Stuempflen, MD, Daniela Prayer, MD, Benjamin Sigl, MD, Mariana Schuette, MD, MD, and Sarah Glatter, MD, M.
M.
Sc
.