by Susan Andrews, PhD
New Evidence That May Help Prevent the Lasting Effects of Early Life Stress
This was a very new topic 10 years ago. Today, however, it is a research area that is receiving much more activity. In 2012, the American Academy of Pediatrics’ position paper acknowledged that the period of time from conception through early childhood is critical. They include prenatal stress in their definition of toxic stress and say that children exposed to early stressful conditions are more likely to struggle in school, have short tempers, manage stress poorly, and tangle with the law.1
A November 2018 Science Daily article titled, “Studies highlight lasting effects of early life stress on the genome, gut, and brain”, starts with a summary statement: “The new research suggests novel approaches to combat the effects of such stress, such as inhibiting stress hormone production or resetting populations of immune cells in the brain.”
In 2012, many articles existed that spoke to the dangers of high levels of stress in pregnant mothers but at that time, the main measures were cortisol production during stress and an understanding that some women (and men) were less able to reduce the effects of stress on their bodies than others. Longitudinal research done in Avon, England had followed pregnant moms and then their offspring until the children became adolescents. Those studies showed strong correlations between highly/chronically stressed mothers (measured by their own ratings) and the propensity of their children to deal less well with stress.
A subsample of 74 of the Avon children at age 10 years old were asked to collect samples of saliva first thing in the morning and at three other times during the day. The samples were collected for three days. Dr. Thomas O’Connor and the study team examined the children’s levels of cortisol and found that the mothers’ levels of prenatal anxiety, some 10 years earlier, predicted the children’s higher morning and afternoon cortisol levels. In other words, the higher the mother’s cortisol levels when she was pregnant, the higher the child’s cortisol levels 10 years later. This study is cited as providing evidence that prenatal anxiety might have lasting effects on the HPA axis functioning in the child and that the child’s HPA axis is affected by the mother’s high cortisol levels during pregnancy.2
What has been more or less missing was a mechanism that made the link between the pregnant mother’s higher cortisol and the child’s higher cortisol levels 10 years later. It is now emerging that there is not one link but many. For example, stress during pregnancy can alter gut bacteria, which can reduce critical nutrients reaching fetuses brains. Even more exciting is that researchers in Tel Aviv University have used cutting-edge genetic research and brain imaging technologies to produce a personal profile of resilience to stress. Their findings hope to lead to a future blood test that would facilitate preventive measures for people with Low Resilience to stress. This could potentially reduce the damaging health consequences and keep us from passing low stress resilience from generation to generation.
1 Jack P. Shonkoff; Andrew S. Garner; and the Committee on Psychosocial Aspects of Child and Family Health; Committee on Early Childhood, Adoptions, and Dependent Care; and Section on Developmental and Behavioral Pediatrics, “The Lifelong Effects of Early Childhood Adversity and Toxic Stress,” Pediatrics 129 (2012): e232–46. 2 Thomas. G O’Connor, Yoav Ben-Shlomo, Jonathan Heron, Jean Golding, Diana Adams, and Vivette Glover, “Prenatal Anxiety Predicts Individual Differences in Cortisol in Pre-Adolescent Children,” Biological Psychiatry 58 (2005): 211–17