Posttraumatic Stress, Depression, Dissociation, and Hypercortisolemia in Pregnancy: A Cohort Study

Purpose: The prevalence of posttraumatic stress disorder (PTSD) in pregnant women is twice as high as in the general female population (8%). In recent reports, PTSD has been associated with lower birth weight and shorter gestation. Animal studies have shown that high levels of maternal stress and abnormalities in hypothalamic-pituitary-adrenal (HPA) axis hormones during pregnancy are associated with prematurity, low birth weight and adverse health outcomes across the lifespan. A similar pattern is emerging from research on humans. However, to date HPA axis function in pregnant women with PTSD has not been well-studied. A profile of hypercortisolemia during pregnancy may be one of the pathways by which maternal PTSD affects obstetric outcomes. This study’s objective is to test the hypothesis that posttraumatic stress disorder (PTSD) is associated with hypercortisolemia in pregnancy.

Methods: This study was conducted as part of a larger prospective cohort study with the overall objective of characterizing PTSD across the childbearing year (NIH R01 NR008767, PI Seng). Participants were English-speaking nulliparous women over 18 who returned salivary cortisol specimens (n=395) fitting cohorts defined as (1) trauma-exposed and PTSD-diagnosed, (2) trauma-exposed, resilient, or (3) non-exposed.  Standardized telephone diagnostic interviews utilizing validated instruments assessed lifetime trauma history, current and lifetime PTSD diagnosis, depression comorbidity, and symptoms of the associated feature of dissociation.  Women collected their own saliva in their homes upon awakening, in late afternoon, and at bedtime.  Radioimmunoassay determined cortisol level.  Repeated measures ANOVA and regression were used to examine HPA axis profiles.

Results: Repeated measures ANOVA indicated that PTSD diagnosis was associated with higher cortisol levels across the afternoon and evening (F[1, 381] = 10.1, p = .002).  Women whose PTSD was comorbid with depression had the highest morning cortisol (F[2, 380] = 6.3, p = .002).  Women whose PTSD included the associated feature of dissociation had the highest levels and flattest circadian curves (F[3, 379] = 4.6, p = .004).

Implications: Maternity care involves a year-long engagement of the woman with a team of professionals, who can encourage her to seek help for posttraumatic mental health needs.  Social work research is just beginning to study PTSD-specific interventions for pregnant women in relation to psychosocial childbearing outcomes, including postpartum mental health and bonding. Addressing PTSD in pregnancy would be worthwhile for the sake of reducing risk behaviors and for improving the mother’s mental health and her infant’s psychosocial development.  Doing so may involve only incremental changes to care systems already in place to address maltreatment history and perinatal mental health needs. Likely, however, it will also be necessary to consider trauma-informed changes to clinical routines and models of care. This will enable providers, including maternity social workers, to better meet the needs of PTSD-affected women who may experience many aspects of pregnancy and labor care as triggering of trauma memories, aversive, or re-victimizing or who have difficulty forming a solid alliance in the maternity care relationship. Improving prenatal care experiences for this population may have benefits that go far beyond increasing their satisfaction.