BALTIMORE, Md. — The dangers of opioid misuse are well documented, but now a new study finds abusing such drugs while pregnant can impact a woman’s child all the way from infancy to their teenage years. Troublingly, researchers say the number of expecting mothers using opioid drugs continues to rise year-over-year.
Researchers at the University of Maryland School of Medicine find opioid exposure in the womb induces long-lasting “impairments” in the brain’s capacity to process sensory information. These brain changes may lead to health conditions including autism, ADHD, or substance abuse issues later on.
To reach these conclusions, scientists observed a group of lab mice after exposing them to fentanyl in the womb. Those rodents showed both withdrawal symptoms and sensory processing disorders from birth all the way through at least adolescence.
“While we had evidence on the effects of fentanyl exposure in newborns, such as premature birth and low birthweight, our study provides new preliminary evidence that the effects of fentanyl last well into adolescence and beyond,” says study author Asaf Keller, PhD, Interim Chair of the Department of Anatomy & Neurobiology, in a university release. “It is a novel and important finding, but one that needs to be replicated in clinical studies.”
Drug misuse during pregnancy is a growing problem
According to data from the Centers for Disease Control and Prevention, roughly seven percent of pregnant women reported using opioids while with child in 2019. Among that group, one in five admitted to misusing their prescribed opioids. Moreover, study authors speculate opioid use in general has likely grown worse over the past year due to the COVID-19 pandemic. There’s data to back up this hypothesis; the CDC reports drug overdose deaths reached their highest recorded levels ever in 2020. The number one drug involved in those deaths? Fentanyl.
In the study, researchers exposed pregnant mice to varying doses of fentanyl while pregnant. They then examined their newborns for the first few weeks of their lives. For mice, a few weeks is enough time to go from a baby to an adolescent in comparison to humans. Newborn mice exposed to the highest levels of fentanyl showed the “most profound” neurological changes. For example, these mice exhibited increased anxiety in response to low-stress situations. Beyond that, study authors also discovered permanent changes to brain circuitry and mechanism cells.
“There were weaker connections in the regions of the brain involved in sensory processing, and stronger connections in regions associated with higher brain processing,” Dr. Keller adds. “We are not at the point of proving causality from the fentanyl exposure, but it is a strong correlation.”
Tying opioid exposure to behavioral issues
Moving forward, the next round of research on this topic should focus on collecting evidence that these documented brain abnormalities lead to tangible changes in behavior. From there, researchers can develop avenues to mitigate these side-effects.
“This is a significant finding that underscores how much we still do not understand about the long-lasting effects of drug exposure to the developing fetus and newborn,” concludes E. Albert Reece, MD, PhD, MBA, Executive Vice President for Medical Affairs at UM Baltimore. “It clearly demonstrates the need for more research to understand fully how such exposure disrupts normal brain development, and to identify therapies that can work to help these children.”
The study is published in JNeurosci: The Journal of Neuroscience.