Association of differential symptoms of stress to hair cortisol and cortisone concentrations among pregnant women in Kenya

Objectives: The purpose of this study was to characterize the stress experienced by pregnant women in Kenya and assess the relationship between perceived stress and stress-related biomarkers of cortisol and cortisone. Background: Kenyan women are exposed to multiple stressors that may result in chronic stress. However, antenatal stress has not been examined and characterized in Kenya; nor has the relationship between pregnant women's self-reported stress and stress biomarkers been established. Methods: One hundred and fifty women were recruited between 22 and 28 weeks gestation. Participants completed the Perceived Stress Scale (PSS) and a sociodemographic questionnaire. Hair samples were obtained for analysis of cortisol and cortisone. Factor analysis was used to extract unique clusters of stress symptoms from items in the PSS. Regression models were computed to examine relationships of stress to cortisone and cortisol, controlling for obstetric risk. Results: Mean age of the women was 25 years (SD = 5, +/- 16-41). Their degree of perceived stress and cortisol/cortisone concentrations both indicated moderate levels of stress. There was no association between general perceived stress and either hair cortisol or cortisone. However, factor analysis of the PSS identified three clusters of stress symptoms and one cluster - a woman's negative frame of mind regarding life and inefficacy in handling its problems - was associated with higher levels of cortisone (beta= -.231, p = 0.011). Conclusions: Specific stress symptoms may have unique relationships to specific biomarkers and be more useful in assessment than general perceived stress. Assays of both hair cortisol and cortisone might enable a more comprehensive assessment of glucocorticoid activity and better prediction of health risks from stress.Lay summary Understanding stress among rural pregnant Kenyan women may help in addressing risks during pregnancy that lead to adverse birth outcomes. Findings suggest that a woman's tendency to think negatively about life and to doubt her ability to handle life's problems are symptoms of stress that may contribute to higher levels of stress hormones. Assessing women's specific symptoms of stress and different stress hormones during pregnancy may more effectively identify women who need intervention to reduce their health risk.