Military sexual trauma interacts with combat exposure to increase risk for posttraumatic stress symptomatology in female Iraq and Afghanistan veterans.

OBJECTIVE: Sexual trauma during military service is increasingly recognized as a substantial public health problem and is associated with detrimental effects on veteran mental health. In this study, we examined associations between childhood trauma, military sexual trauma (MST), combat exposure, and military-related posttraumatic stress symptomatology (PTSS) in the Women Veterans Cohort Study (WVCS), a community-based sample of veterans who served in the recent conflicts in Iraq and Afghanistan.

METHOD: From July 2008 to December 2011, 365 female veterans completed a survey that assessed combat exposure, military sexual trauma, military-related PTSS (assessed using the PTSD [posttraumatic stress disorder] Checklist-Military Version), and demographic, life history, and other psychopathology variables.

RESULTS: High rates of childhood trauma (59.7%) and MST (sexual assault = 14.7%; sexual harassment = 34.8%) were observed in this sample. A hierarchical regression revealed that active duty status, childhood trauma, combat exposure, and MST were independently associated with increased severity of military-related PTSS (Ps < .05). Moreover, a significant interaction emerged between MST and combat exposure in predicting military-related PTSS (P = .030), suggesting that the relationship between combat exposure and PTSS was altered by MST status. Specifically, under conditions of high combat exposure, female veterans with MST had significantly higher PTSS compared to female veterans without MST.

CONCLUSIONS: Taken together, results suggest that exposure to multiple traumas during military service may have synergistic effects on posttraumatic stress symptoms in female veterans. Moreover, our findings highlight the importance of prevention efforts to protect female veterans from the detrimental effects of MST, particularly those who are exposed to high levels of combat.