Childhood stress and birth timing among African American women: Cortisol as biological mediator

Abstract

Preterm birth (PTB) occurs among 1:11 U.S. white women and 1:7.5 African American women and is a significant driver of racial disparities in infant mortality. Maternal stress is the most common clinical phenotype underlying spontaneous PTB. Specific patterns of stress and biological mediators driving PTB remain unclear. We examined the effect of childhood stress on birth timing among African American women and evaluated maternal cortisol elevation as a biological mediator. A prospective observational design was employed, with a single study visit at 28–32 weeks gestation and medical record review. The Stress and Adversity Inventory was administered, which provides a comprehensive estimate of childhood stress, stress in adulthood, and five core characteristic subscales (interpersonal loss, physical danger, humiliation, entrapment, role disruption). Venipuncture was performed between 11:00am and 4:00pm and plasma cortisol quantified by ELISA. Analyses controlled for stress in adulthood. Among a final sample of 89, cumulative childhood stress predicted birth timing (p = .01). The association was driven by stress related to interpersonal loss and physical danger, with support for maternal cortisol as a biological mediator (ab = 0.02, 95% CI [0.001, 0.045]; ab = 0.02, 95% CI [0.001, 0.043], respectively). Results were similar, overall, in sub-group analyses among spontaneously laboring women (n = 53); however, role disruption arose as an additional predictor, as mediated by cortisol elevations (ab = 0.03, 95% CI [0.005, 0.074]). Of note, cortisol was no longer supported as a mediator linking physical danger to birth timing after adjusting for sleep quality and hours awake prior to venipuncture (ab = 0.02, 95% CI [−0.0001, 0.046]). We provide preliminary evidence that, independent of stress in adulthood, childhood stress of specific core characteristics may shape birth timing, with cortisol elevation as a biological mediator. Further investigation is warranted and may bolster the development of biologically-informed screening tools for the prediction and targeted prevention of stress-related PTB.

Maternal parity and perinatal cortisol adaptation: The role of pregnancy-specific distress and implications for postpartum mood

“…Similarly, for the quantification of serum cortisol levels, whole blood was collected at three time points across pregnancy and at postpartum and standardized according to time of day. As in the current study, prior work has demonstrated associations between psychological stress and circulating levels of cortisol during pregnancy, including under experimental conditions using animal models and per self-report during human gestation (Gillespie et al, 2017; Szenci et al, 2011). Use of the well-validated Revised Prenatal Distress Questionnaire (Lobel et al, 2008; Yali and Lobel, 1999) was also a strength of the study, as the 17-item instrument provides an estimate of pregnancy-specific distress, a unique construct.…”

Stress and the HPA Axis: Balancing Homeostasis and Fertility

“…A population-based study in Denmark also described an association between a stressful life event occurring within the six months prior to conception and an increased risk for preterm delivery [ 74 ]. In a small study of African-American women, childhood stress, independent of stress in adulthood, was associated with early birth timing [ 75 ]. Women experiencing high levels of psychosocial stress during pregnancy are at significantly increased risk for shortened gestation and preterm delivery, even after accounting for the effects of established risk factors such as sociodemographic, biophysical, biomedical, and behavioral [ 76 ].…”

Childhood adversity impact on gut microbiota and inflammatory response to stress during pregnancy

“…While recent research from our laboratory indicates dysregulated HPA response among high ACE women postpartum (Morrison et al, 2017), ACE impact on inflammatory response to stress has not been studied during pregnancy. Maternal ACE history is associated with lower offspring gestational age and weight at delivery (Smith et al, 2016), and recent work suggests maternal cortisol (Gillespie et al, 2017) or elevated baseline interleukin (IL)-6 (Miller et al, 2017) may mediate this. Intriguingly, emerging rodent research indicates that early life stress also alters the gut microbiome (Jašarević et al, 2017, 2015), and the gut microbiome is known to influence inflammation and HPA axis function (Sudo, 2014).…”