Pregnancy Depression Impacts Stress Hormones of Babies
Depression during pregnancy has many health implications, including a new effect seen in babies born to depressed mothers. Research from the University of Michigan School of Medicine has found that these babies have higher levels of stress hormones, decreased muscle tone, and other neurological and behavioral differences.
Pregnancy and Postpartum Depression Has Many Health Effects on Children
Lead investigator Dr. Delia M. Vazquez, a professor of psychiatry and pediatrics, and colleagues studied 154 pregnant women over the age of 20 who had depressive symptoms assessed at 28, 32, and 37 weeks of pregnancy and again after they gave birth. Blood samples were taken from the umbilical cord to measure stress hormone levels. The infants then underwent neurobehavioral tests at two weeks to assess motor skills and response to stimuli and stress.
The tests were used to measure the development of the infants’ neuroendocrine system, which controls the body’s stress response, as well as mood and emotions.
From the umbilical cord samples, the researchers found that the babies born to depressed mothers had elevated levels of adrenocorticotropic hormone (ACTH), which controls the adrenal gland’s production of the stress hormone cortisol. The researchers do note that elevated cortisol could also be attributed to the high level stress associated with birth.
At two weeks, the children of the depressed mothers had lower muscle tone compared to those born to mums who weren’t depressed, but they adjusted more quickly to a stimuli such as a bell, rattle or light. This is considered a sign of neurological maturity.
Dr. Vazquez suggests two possibilities for the effect. “The infants are either more sensitive to stress and respond more vigorously to it, or…they are less able to shut down their stress response,” she says.
Author Sheila Marcus, the clinical director of U-M’s Child and Adolescent Psychiatry Section, stresses that the investigation is still preliminary and that “it’s difficult to say to what extent these differences are good or bad, or what impact they might have over a longer period of time. We’re just beginning to look at these differences as part of a whole collection of data points that could be risk markers.”