Prenatal traumatic stress and offspring hair cortisol concentration: A nine year follow up to the Red River Flood Pregnancy Study

Authors: STRAHM, ANNA - North Dakota State University; BAGNE, ANGELA - North Dakota State University; RUED, HEIDI - North Dakota State University; Larson, Kate; Roemmich, James; HILMERT, CLAYTON - North Dakota State University

Submitted to: Psychoneuroendocrinology
Publication Type: Peer Reviewed Journal
Publication Acceptance Date: 12/23/2019
Publication Date: 1/7/2020
Citation: Strahm, A., Bagne, A., Rued, H., Larson, K.J., Roemmich, J.N., Hilmert, C. 2020. Prenatal traumatic stress and offspring hair cortisol concentration: A nine year follow up to the Red River Flood Pregnancy Study. Psychoneuroendocrinology. https://doi.org/10.1016/j.psyneuen.2019.104579.
DOI: https://doi.org/10.1016/j.psyneuen.2019.104579

Interpretive Summary: Psychological stress experienced during the maternal prenatal period may affect the stress reactivity of the child. Cortisol is a ‘stress’ hormone that signals the occurrence of psychological stress. However, it remains unclear whether maternal prenatal stress ‘programs’ the child offspring to be more stress reactive. Scientists from the Grand Forks Human Nutrition Research Center in collaboration with those from North Dakota State University studied whether the magnitude of stress during pregnancy, measured as the distance from a natural flood disaster, helped to understand the association between prenatal maternal cortisol and hair cortisol concentrations of the offspring when they were 9 years old. The research found that experiencing a traumatic stressor during pregnancy may alter maternal-fetal programming of cortisol release.

Technical Abstract: Introduction: Findings concerning the relationship between maternal prenatal and child cortisol concentrations is inconsistent, implicating unaccounted for moderators of this association. This study examined whether the influence of an objective traumatic stressor during pregnancy, distance from a natural flood disaster, moderated the association between prenatal maternal diurnal cortisol area under the curve (AUC) and 9-year old offspring hair cortisol concentrations. Methods: Data were collected from 56 of the mothers who took part in a study of flood-related pregnancy outcomes in 2009 and their children. Data included distance of the maternal home from flooding areas, four maternal saliva cortisol assessments (waking, 30minutes after waking, afternoon, and before bed) provided within 3-months of the flood crest and used to calculate diurnal AUC, and child hair samples to assess cortisol secretion over the past month Results: There was a significant interaction between proximity to flooding during pregnancy and maternal cortisol AUC predicting child hair cortisol. At greater distance from flooding (i.e. lower stress conditions) there was a positive association between maternal cortisol and child cortisol. In contrast, living closer to flooding (i.e. higher stress conditions) produced a significant negative association between maternal and child cortisol. Conclusion: Experiencing a traumatic stressor during pregnancy may alter maternal-fetal programming of the hypothalamic-pituitary-adrenal axis. The direct threat of flooding led to a maternal and offspring cortisol association that resembled associations seen in mothers with symptoms of PTSD and their offspring. This alteration is evident in nine-year-old offspring and may help explain inconsistencies in the previous literature.