A recent MRI study revealed that consumption of alcohol even in low to moderate amounts while pregnant can change the child’s brain structure and delay brain development. Results of the study will probably be presented next week on the annual meeting of the Radiological Society of North America (RSNA).

Fetal MRI is a highly specialized and secure examination method that enables us to make accurate statements about brain maturation prenatally.”

Gregor Kasprian, M.D., study senior writer, associate professor of radiology, Department of Biomedical Imaging and Image-guided Therapy of the Medical University of Vienna in Austria

Alcohol consumption while pregnant can expose the fetus to a gaggle of conditions called fetal alcohol spectrum disorders. Babies born with fetal alcohol spectrum disorders could develop learning disabilities, behavioral problems or speech and language delays.

“Unfortunately, many pregnant women are unaware of the influence of alcohol on the fetus while pregnant,” said lead writer Patric Kienast, M.D., a Ph.D. student within the Department of Biomedical Imaging and Image-Guided Therapy, Division of Neuroradiology and Musculoskeletal Radiology on the Medical University of Vienna. “Subsequently, it’s our responsibility not only to do the research but additionally to actively educate the general public in regards to the effects of alcohol on the fetus.”

For the study, researchers analyzed MRI exams of 24 fetuses with prenatal alcohol exposure. The fetuses were between 22 and 36 weeks of gestation on the time of MRI. Alcohol exposure was determined via anonymous surveys of the moms. The questionnaires used were the Pregnancy Risk Assessment Monitoring System (PRAMS), a surveillance project of the Centers for Disease Control and Prevention and health departments, and the T-ACE Screening Tool, a measurement tool of 4 questions that discover risk drinking.

In fetuses with alcohol exposure, the fetal total maturation rating (fTMS) was significantly lower than within the age-matched controls, and the suitable superior temporal sulcus (STS) was shallower. The STS is involved in social cognition, audiovisual integration and language perception.

“We found the best changes within the temporal brain region and STS,” Dr. Kasprian said. “We all know that this region, and specifically the formation of the STS, has an important influence on language development during childhood.”

Brain changes were seen within the fetuses even at low levels of alcohol exposure.

“Seventeen of 24 moms drank alcohol relatively infrequently, with average alcohol consumption of lower than one alcoholic drink per week,” Dr. Kienast said. “Nevertheless, we were capable of detect significant changes in these fetuses based on prenatal MRI.”

Three moms drank one to 3 drinks per week, and two moms drank 4 to 6 drinks per week. One mother consumed a mean of 14 or more drinks per week. Six moms also reported at the least one binge drinking event (exceeding 4 drinks on one occasion) while pregnant.

Based on the researchers, delayed fetal brain development could possibly be specifically related to a delayed stage of myelination and fewer distinct gyrification within the frontal and occipital lobes.

The myelination process is critical to brain and nervous system function. Myelin protects nerve cells, allowing them to transmit information faster. Vital developmental milestones in infants, as rolling over, crawling and language processing are directly linked to myelination.

Gyrification refers back to the formation of the folds of the cerebral cortex. This folding enlarges the surface area of the cortex with limited space within the skull, enabling a rise in cognitive performance. When gyrification is diminished, functionality is reduced.

“Pregnant women should strictly avoid alcohol consumption,” Dr. Kienast said. “As we show in our study, even low levels of alcohol consumption can result in structural changes in brain development and delayed brain maturation.”

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

“To evaluate this accurately, we’d like to attend for the youngsters who were examined as fetuses at the moment to get a little bit older, in order that we will invite them back for further examinations,” Dr. Kienast said. “Nevertheless, we will strongly assume that the changes we discovered contribute to the cognitive and behavioral difficulties which will occur during childhood.”

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

Source:

Radiological Society of North America