The relation between early life adversity, cortisol awakening response and diurnal salivary cortisol levels in postpartum women.

Early life adversity has been associated with hypothalamic-pituitary-adrenal (HPA) axis dysfunction in both children and adults. However, in adulthood, most studies have focused on the effects of early adversity on HPA axis stress reactivity rather than the cortisol awakening response or diurnal cortisol profiles. The goal of this study was to examine the cumulative effects of early life adversity on the cortisol awakening response (CAR) and diurnal cortisol profiles in a sample of postpartum women. Ninety women between 2 and 6 months postpartum completed two retrospective reports assessing adverse early life experiences (maltreatment and consistency of care). Eighteen women reported having experienced both parental loss and some form of childhood maltreatment and 36 women reported having experienced one type of early life adversity, either parental loss or maltreatment. HPA axis function was assessed through salivary cortisol collections over two consecutive days for measurement of the cortisol awakening response (n=61) and diurnal cortisol rhythm (n=90). Women who reported experiencing adverse early life experiences exhibited a tendency towards higher levels of awakening cortisol compared to women who reported no adverse early life experiences (p=.07). These higher awakening cortisol levels were sustained throughout the morning in the groups who experienced early adversity, with all groups exhibiting the typical diurnal decline in the afternoon and evening (p<.05). Women reporting early adversity exhibited more heterogeneity in their diurnal cortisol levels across the two collection days (p<.01). Our findings suggest that in a community sample of postpartum women, early adversity is associated with current HPA axis function. These findings may have implications for the nature of mother-infant interactions.

Maternal early life experiences and parenting: the mediating role of cortisol and executive function.

OBJECTIVE: Research suggests that early life adversity may affect subsequent parenting. Animal studies investigating mechanisms of transmission have focused on biological factors; whereas research in humans has emphasized cognitive and psychosocial factors. We hypothesized that neuropsychological and physiological factors would act as mediators between maternal retrospective reports of early life experiences (ELE) and current parenting. METHOD: We recruited a community sample of 89 mothers and their infants (2-6 months of age). Maternal ELE consisted of self-reports of consistency of care and childhood maltreatment. Diurnal salivary cortisol samples were collected as the measure of hypothalamic-pituitary-adrenal (HPA) function. Executive function measures included attentional set-shifting and spatial working memory. Maternal sensitivity was assessed through videotapes of mothers interacting with their infants. RESULTS: A series of path analyses indicated that maternal ELE was indirectly related to maternal sensitivity via two pathways: one through HPA function, and the other through HPA function and spatial working memory. There was no direct path between maternal ELE and parenting. CONCLUSION: These findings provide support for the notion that mediators linking early life experiences to parenting in humans may be similar to physiological mechanisms found in animal models. As maternal care is associated with numerous infant outcomes, our findings may have broad relevance to understanding the risk associated with parenting and adverse outcomes in infants. A greater understanding of mechanism is important to informing interventions targeted at disrupting maladaptive trajectories of parenting.