Bridging the Silos: Connections Between Trauma Exposure, Posttraumatic Stress, and Depression in a Community Sample of First-Time Mothers

Background/Purpose: The prevalence of posttraumatic stress disorder (PTSD) in pregnant women is twice as high as in the general female population (8%). PTSD has been associated with lower birth weight, shorter gestation, and impaired mother/infant bonding. Postpartum depression has also been shown to have adverse effects, including impaired mother/infant bonding and insecure attachments, poor infant cognitive performance, maternal perception of infants as more difficult temperamentally, increased rates of compromised caregiving, and suicide.

Researchers have noted the difficulty of diagnosis and treatment for women affected by the comorbidity of PTSD and depression; yet currently researchers and clinicians appear to be operating in distinct “silos,” meaning that this comorbidity is not being specifically addressed. The specific aim of this study is to determine the extent to which it is warranted to integrate perinatal mental health research focus and clinical care to combine attention to depression, trauma, and posttraumatic stress.

Methods: This study is a secondary analysis of a larger prospective cohort study of PTSD across the childbearing year. Participants were 1581 English-speaking women over 18 who were pregnant for the first time. Standardized telephone diagnostic interviews collected sociodemographic information and utilized validated instruments in order to assess lifetime trauma history, PTSD, major depressive disorder (MDD), and other comorbid disorders. Statistical methods used included multinomial logistic regression and receiver-operator growth curve modeling (ROC) techniques.

Results: A multinomial logistic regression model considered which types of sociodemographic factors, specific types of trauma exposures, and comorbid disorders would predict membership in categories based on 1) endorsement of a trauma that met the DSM-IV PTSD criteria, 2) PTSD diagnosis, and 3) MDD diagnosis.  The model was statistically significant (-2 LL 2631.292, X² = 1671.61, df 55, p<.001, Nagelkerke pseudo R² = .70). Sociodemographic challenges and trauma exposures were spread across all categories. Differences in the kinds of traumatic exposures emerged between those women with a DSM-IV “qualifying” trauma exposure and depression versus those women without a “qualifying” trauma exposure. However, it appears that those differences may be largely accounted for by sub-threshold PTSD; meaning that the participant reported some symptoms but did not meet full PTSD diagnostic criteria.

Longitudinal ROC analyses showed that prenatal depressive probability scores were the least adequate predictor of postpartum depression, and that trauma exposure history alone, PTSD symptom count alone, or the combination of trauma exposure history and PTSD symptom count were better predictors of postpartum depression.

Conclusions/Implications: These analyses show a distinct relationship between mental health in pregnancy and mental health during the postpartum period. However, this relationship is characterized by the interplay between trauma exposure, PTSD, and depression. This underscores the need to bridge the silo between PTSD and MDD research and to bring a trauma-specific lens to both research and clinical foci. Understanding who is at risk for what may help researchers design more effective interventions, and encourage social workers, infant mental health specialists, and others who provide mental health services to parturient women to consider trauma-informed and trauma-specific modalities for working with depression during the childbearing year.