UCSF-led study shows that a mother’s stress significantly increases likelihood of illness in her infant.
Listen for a heartbeat. Wait for a cry. Count 10 fingers. Check for 10 toes. In the delivery room, these are the steps a mother often takes to confirm the health of her newborn child. Yet the seeds for a healthy life are planted long before the child is born.
We know that chronic or long-term stress in adults wears out cells and has been linked with chronic conditions including heart disease and diabetes. But how does maternal stress affect infants?
Nicole “Nicki” Bush, PhD – whose research integrates insights from social epidemiology, sociology, clinical psychology, developmental psychobiology, genetics, and epigenetics to understand their effect on youth development – seeks to answer that very question.
Along with her colleagues in the UCSF Department of Psychiatry and at UCSF Benioff Children’s Hospitals and the UCSF Weill Institute for Neurosciences, Dr. Bush completed a study in 2020 that sheds light on the link between a mother’s mental well-being and her infant’s physical health, specifically focused on stress.
The study involved 109 low-income, racially and ethnically diverse, overweight and obese women with an average age of 28 years from the longitudinal Stress, Eating, and Early Development (SEED) study. The women rated on a five-point scale how stressed they felt by challenges in their lives during middle and late pregnancy. The researchers later assessed the health of the infants across their first year of life by examining their medical records.
The research team found that for every one-point increase in reported prenatal maternal stress, there was a 38% increase in infectious illness, a 73% increase in noninfectious illness, and a 53% increase in variety of illnesses among the infants. They also saw that postnatal stress and depression in the mothers were not associated with any additional increase in illness among the infants, after considering prenatal stress effects.
“These results are in line with a growing body of research indicating that stress to the mother during pregnancy – especially in late pregnancy – has a negative impact on the health of the baby, independent of whatever stress or emotional challenges the mother might experience after giving birth,” Dr. Bush says.
She noted that 60%-68% of the study’s participants were overweight or obese. “Our sample may actually be more representative of American mothers than typical research populations, and that is one value of this work,” she says. “We need samples that represent mothers who are most likely to experience high levels of stress during pregnancy if we are to understand and prevent intergenerational transmission of risk for poor health.”
Nicole Bush, PhD, is director of the UCSF Division of Developmental Medicine, associate professor in the UCSF Department of Psychiatry and Behavioral Sciences and Department of Pediatrics, and the Lisa and John Pritzker Distinguished Professor of Developmental and Behavioral Health.
The study was published Aug. 19, 2020, in the Journal of Pediatrics. The last author of the study is Elissa Epel, PhD, professor and vice chair in the UCSF Department of Psychiatry. Co-authors are Nancy Adler, PhD; W. Thomas Boyce, MD; Michael Coccia, MS; and Karen Jones-Mason, JD, MSW, PhD, of UCSF; Jennifer Savitz, MD, of UCSF, the University of Washington, and Seattle Children’s Hospital; and Barbara Laraia, PhD, of UC Berkeley.