A mom's high stress levels during pregnancy might make their kids age faster, a study suggests

• Researchers found that children whose mothers experienced high levels of stress during pregnancy aged faster than scientists would expect.
• The same research team found that a mother's mental well-being — even before pregnancy — can impact her risk for premature birth.
• Study authors say the findings underscore the need to support at-risk mothers to reduce the risk of chronic health conditions for their children.

If a mother experiences lots of stress during pregnancy, her child may age faster throughout their lives, potentially increasing their risk for chronic conditions like high blood pressure, diabetes and cardiovascular disease.

That's according to a study published last month in the journal Psychoneuroendocrinology. The research was conducted by scientists at the University of California, Los Angeles (UCLA) who followed 111 women from before conception until their children were three to five years old.

The team found that women who reported more stress during pregnancy had children with shorter buccal telomere length. Telomeres are protective parts of the DNA strand, and shorter telomeres length has been linked to chronic diseases and premature death, according to a UCLA press release.

In short, a mother's stress during pregnancy may cause her children to age faster, explained lead study author Judith Carroll, an associate professor of psychiatry and biobehavioral sciences at UCLA.

"What our research tells us is that we may have early environmental and maternal factors influencing where a person starts in life, which may set them on course to age faster," Carroll said in the press release.

Stressors during the third trimester were particularly powerful in shortening a child's telomere length, the researchers found.

The study didn't look at the reason for why stress affects telomere length and thus speeds aging. However, Carroll offered a theory: stress is linked to inflammation, which in turn can damage DNA, she said. The child's DNA could be damaged by the mother's response to stress during pregnancy, resulting in shorter telomeres and premature aging.

The impacts of stress can be passed through generations

Stress can have a negative impact on health, affecting everything from mental health to cardiovascular disease risk. There's also a lot of evidence that the physical effects of stress can be passed through generations.

Scientists believe that the stress experienced by your parents or even grandparents experience could change your genes. Researchers are still working to understand exactly how this happens, and how much of a role it plays in the development of chronic conditions. The new study may give some insight, by showing a specific biological change that kids experience when their mothers are stressed during pregnancy.

Understanding the ways that disease risk and stress are passed intergenerationally could help scientists better understand how to prevent disease and address racial and socio-economic disparities in disease rates.

A mother's stress even before pregnancy could impact premature birth

A second study by the same UCLA research group found that women who experienced high levels of stress - even in the years before pregnancy - were more likely to give birth early. Premature birth is linked with a host of negative health outcomes for a child throughout their lifetime, from digestive issues to intellectual disabilities.

This study, published in the Annals of Behavioral Medicine, was much larger, following more than 2,600 women. Even when the researchers controlled for pre-existing medical conditions that the mothers had, moms with higher stress levels gave birth, on average, a week earlier than those who didn't report high stress levels.

"What we have not known until now is whether a mother's psychosocial health before conception matters for her birth outcomes," said study author Christine Dunkel Schetter, a professor of psychology and psychiatry at UCLA, in a press release. "This study is among the first to point out that, yes, it does matter."

Most of the women in the study were low-income, living near the poverty line. The findings give scientists a better understanding of how socioeconomic status can impact chronic disease.

Taken together, the two studies show that addressing the overall health of women before and during pregnancy could improve health outcomes for generations.