A new study has found that even brief drops in oxygen levels experienced by premature babies in intensive care could have lasting effects on brain development, potentially impacting learning and memory well into adolescence and adulthood.

The research, led by Dr. Stephen Back, a professor of pediatrics at Oregon Health & Science University in Portland, highlights the risks associated with intermittent hypoxia — short, repeated episodes of low oxygen levels in body tissues.

“Just one bad day in the NICU could be enough to alter the course of brain development for life,” Dr. Back said.

Premature babies are particularly vulnerable to such episodes due to underdeveloped lungs, which can limit the supply of oxygen to vital organs and tissues. While earlier research has largely focused on severe or prolonged oxygen deprivation, this study is among the first to examine the effects of mild, intermittent hypoxia on the developing brain.

Published in The Journal of Neuroscience on March 23, the study used a mouse model to better understand these effects. Researchers found that even mild oxygen disruptions interfered with critical brain functions, particularly in the hippocampus — the region responsible for learning and memory.

The study revealed that communication between the hippocampus and the cortex, which plays a key role in reasoning and problem-solving, was significantly impaired. Additionally, nerve cells in the hippocampus failed to develop properly and showed no signs of full recovery, even into adulthood.

Experts say this disrupted communication network could have wide-ranging consequences, affecting not only learning and memory but also essential functions such as movement, breathing, and emotional regulation.

Dr. Cindy McEvoy, a pediatric specialist involved in the study, noted that these changes are not easily detectable during routine neonatal care. “These impacts occur deep within the brain’s connections and may only become apparent years later as the child grows,” she explained.

Although the findings are based on animal research and may not directly translate to humans, they raise important concerns about the long-term effects of even mild oxygen deprivation in premature infants.

Researchers believe that early identification of at-risk children could help doctors intervene sooner, offering targeted support to improve developmental outcomes.

If confirmed in human studies, the findings could lead to changes in neonatal care practices, including increased use of respiratory support methods like continuous positive airway pressure (CPAP) to prevent oxygen fluctuations.