12/11/2025
A new study shows that high maternal stress during pregnancy can molecularly reprogram a newborn’s stress-response system. Researchers discovered that stress alters tRNA fragments (tRFs) in umbilical cord blood, affecting brain function and immune regulation.
The changes were especially pronounced in female newborns, while boys showed elevated levels of acetylcholinesterase (AChE), an enzyme that breaks down acetylcholine, signaling differences in how stress affects each s*x from birth. Using machine learning, scientists could identify babies exposed to prenatal stress with 95% accuracy.
These findings highlight the importance of supporting maternal mental health, as stress during pregnancy can impact a child’s long-term neurodevelopment and risk for psychiatric conditions. Early detection could lead to better interventions and healthier outcomes for both mother and child.
Source / Credit: Hebrew University of Jerusalem, Prof. Hermona Soreq & Shani Vaknine Treidel (2025), Nature Communications
