Past violence and brain injury amplify mental health vulnerability after childbirth

Toronto, ON, April 29, 2026 — The risk of new and severe postpartum mental illness is highest among people who experienced both traumatic brain injury (TBI) and interpersonal violence compared to those with neither factor. The next highest risk is among individuals who experience interpersonal violence alone, followed by those with a history of TBI only. 

A TBI occurs when an external force damages the brain and can lead to mild to severe physical and psychological effects, including an elevated risk of mental illness. Besides falls and motor vehicle crashes, another common cause of TBI is interpersonal violence, with more than 60 per cent of these incidents resulting in a TBI-related diagnosis. 

The study, led by researchers from ICES, examined 1,090,139 births in Ontario between 2012 and 2021. They found that among those with a history of both TBI and interpersonal violence who did not receive mental health care in the two years prior to giving birth, nearly one in five (21.5 per cent) were at risk of new episodes of mental illness. Even among those who had received mental health care, the risk of severe postpartum mental illness—defined as one or more psychiatric emergency department visits or hospital admissions—was highest for individuals with a history of both TBI and interpersonal violence, at 14.1 per cent.  

“Exposure to trauma over time can make the brain more susceptible to mental illness,” says Dr. Hilary Brown, Scientist at ICES and Associate Professor in the Department of Health and Society at the University of Toronto Scarborough. “When sleep deprivation, hormonal fluctuations, and other stressors associated with childbirth are added, these factors combined with past trauma can have more profound effects and further heighten this vulnerability.” 

“Given the significant long-term risks to mother and child, it is crucial to implement healthcare and social supports that are trauma-informed, person-centred, and culturally sensitive,” adds Brown. 

To better support patients with TBI and history of interpersonal violence and minimize harm, the researchers recommend that healthcare providers adopt trauma- and violence-informed approaches to care. Resources such as the “Abused and Brain Injured” toolkit (www.abitoolkit.ca) can help providers foster patient safety and trust.  

The study “Traumatic brain injury, interpersonal violence, and postnatal mental illness: population-based study” is in the April issue of Social Psychiatry and Psychiatric Epidemiology.  

ICES is an independent, not-for-profit research and analytics institute that uses population-based health information to produce knowledge on a broad range of healthcare issues. ICES leads cutting-edge studies and analyses evaluating healthcare policy, delivery, and population outcomes. Our knowledge is highly regarded in Canada and abroad and is widely used by government, hospitals, planners, and practitioners to make decisions about healthcare delivery and to develop policy. For the latest ICES news, follow us on BlueSky and LinkedIn: @ICESOntario    
 

FOR FURTHER INFORMATION PLEASE CONTACT:    
Charlotte Lam    
Communications Associate   
ICES     
[email protected]   
437-317-8804