Pregnant and Stressed? New research reveals SHOCKING impact of stress on unborn babies

Pregnancy is one of the most vital periods in any woman’s life due to the profound physical, psychological, and social changes it brings. It's a time of immense growth, not just for the fetus, but also for the mother as she adapts to hormonal shifts, physical changes, and the emotional and psychological adjustments of motherhood.

Apart from that, pregnancy can be a concerning period for many women due to the numerous physical, emotional, and social changes it brings. These changes include significant hormonal fluctuations, potential health risks like gestational diabetes or preeclampsia, and the constant worry about the well-being of the developing baby. Additionally, pregnancy can impact a woman's body image, work life, and relationships, creating a complex web of concerns and anxieties.


To sum it up, it can be pretty challenging to sail through the time period without its trials and tribulations. Naturally, it can be a fairly stressful time for the new mothers as well.

However – no matter how inevitable it might be – the would-be mothers should try their best to do without the stress.


Why so?


According to a new study, stress experienced by mothers during pregnancy leaves a molecular imprint on their babies, starting before birth.


Read on to know more.


What does the study say?

A new study reveals that stress experienced by mothers during pregnancy can affect their babies even before birth. Researchers found that this prenatal stress changes small RNA molecules in the blood of newborns, especially in girls.

This may explain why some children are more at risk for developmental or mental health issues later in life. The study opens new possibilities for identifying and addressing health risks related to stress early on.

This research was conducted as a part of the international FELICITy project, in collaboration with the Technical University of Munich and the University of Washington, among others.

The research team analyzed blood samples from over 120 mother-infant pairs at the Hebrew University’s Center for Genomic Technologies.

The study, led by Professor Hermona Soreq and Shani Vaknine Treidel from the Edmond and Lily Safra Center of Brain Science at Hebrew University, focused on how a mother's perception of stress during pregnancy can alter important biological pathways in her baby. These pathways are linked to the cholinergic system, which is responsible for how the body responds to stress and inflammation.


Prof. Soreq stated, "Even before babies take their first breath, the stress their mothers experience can shape how their bodies manage stress themselves."

The researchers analyzed umbilical cord blood from babies born to mothers who reported high stress levels in the third trimester. They looked at small RNA molecules called tRNA fragments, which help control gene expression. Remarkably, the stress impacted whole families of tRNA fragments, especially those from mitochondrial DNA.


What are the findings of the study?

The findings were different by sex, with female newborns showing the biggest changes, including a near-total decrease in certain mitochondrial tRNA fragments. Many of these fragments, known as "CholinotRFs," target genes that control acetylcholine, an important neurotransmitter for brain function and immune system regulation.

The study also measured levels of acetylcholinesterase (AChE), an enzyme that breaks down acetylcholine. Newborns of stressed mothers, especially boys, had much higher AChE levels, indicating an imbalance in their stress-response system right from birth.


These biological changes might help explain why children exposed to high maternal stress during pregnancy could be more prone to neurodevelopmental and mental health conditions later on. Using machine learning, the researchers could classify female newborns as exposed or unexposed to maternal stress based on their CholinotRF profiles, achieving a success rate of 95%. This paves the way for new diagnostic tools to detect the effects of prenatal stress and possibly even early interventions.

As per Vaknine Treidel, "This study provides a powerful look at how the maternal environment can leave a lasting biological impact on the next generation. It also highlights the importance of supporting mental health during pregnancy—not just for the mother, but for the lifelong health of the child."