Women with severe childhood trauma show unique stress hormone patterns

A new study suggests that women whose most distressing traumatic experiences occurred during childhood respond differently to biological stress than men or women traumatized later in life. The research indicates that these women exhibit a muted hormonal response to stressful situations, a pattern not observed in male participants. These results were published in the Journal of Traumatic Stress.

Trauma impacts a vast number of people globally. Women, however, are disproportionately affected by the psychological aftermath of these events. Statistics show that women are roughly twice as likely as men to develop posttraumatic stress disorder, or PTSD, during their lifetimes. Research indicates that this disparity cannot be explained simply by the amount of trauma women face.

Scientists have historically struggled to pinpoint the biological reasons for this gap. One major hurdle has been the tendency of biomedical research to focus primarily on male physiology. This practice effectively treats women as “small men,” ignoring the unique hormonal and biological environments of the female body. Consequently, the mechanisms that link trauma to physical health outcomes in women remain poorly understood.

The body responds to stress through a system known as the hypothalamic-pituitary-adrenal axis. This system releases cortisol, often called the stress hormone, to help the body manage threats. In a healthy response, cortisol levels spike when a person faces a challenge and then return to baseline.

In some individuals with a history of trauma, this system functions distinctively. Instead of rising to meet a challenge, cortisol levels may remain low. This phenomenon is known as “blunted” cortisol reactivity. This muted response is associated with various negative health outcomes, including anxiety, depression, and autoimmune disorders.

Researchers at Wayne State University School of Medicine sought to clarify how sex interacts with this stress response. The team included experts from the departments of Psychiatry and Behavioral Neurosciences, Theoretical and Behavioral Foundations, and Sociology. They aimed to determine if the timing or type of trauma influences cortisol patterns differently in men and women.

The study also investigated the role of subjective perception. The researchers wanted to know if the event a person considers their “worst” trauma matters more than simply tallying a list of bad experiences. This approach recognizes that the impact of a traumatic event can vary widely from person to person.

To test these ideas, the team recruited 59 adults from the Detroit area. The group consisted of 37 women and 22 men. All participants had a history of trauma exposure. The researchers screened the participants to exclude those with medical conditions or medication regimens that might artificially alter hormone levels.

The participants underwent a standardized laboratory procedure called the Trier Social Stress Test. This test is designed to induce moderate psychosocial stress in a controlled environment. First, participants had to perform a mock job interview in front of a panel of “behavior experts.”

The participants were told that these experts were evaluating their performance. Following the interview, the participants were asked to complete a surprise mental arithmetic task. Throughout the 90-minute session, the researchers collected saliva samples at five specific time points. These samples allowed the team to measure the total amount of cortisol released and the change in levels over time.

Participants also completed detailed questionnaires regarding their history. They used the Stressful Life Events Screening Questionnaire to report which events they had experienced. Crucially, they were asked to identify the single “most stressful or upsetting event” of their lives. This was labeled the “index event.”

The researchers categorized these index events based on when they happened. They distinguished between traumas that occurred during childhood, defined as before age 18, and those that happened in adulthood. They also classified the events by type. Interpersonal traumas included events like physical or sexual assault. Non-interpersonal traumas included events like car accidents or natural disasters.

The analysis revealed distinct biological patterns based on sex. In the male group, the timing of the trauma did not predict cortisol patterns. Men who identified childhood trauma as their worst experience showed similar stress responses to those who identified adult trauma.

For women, the results were distinct. Women who identified a childhood event as their most stressful life experience showed a blunted cortisol response. Their bodies did not produce the expected rise in stress hormones during the mock interview and math task. This effect was substantial.

It is important to note that this association was specific to the subjective “index event.” Women who had objectively experienced childhood trauma but identified an adult event as their most stressful did not show this blunted response. This suggests that the subjective impact of early-life trauma is a key factor in how the female stress system functions.

The study did not find a similar link regarding the type of trauma. Whether the event was interpersonal or non-interpersonal did not statistically predict cortisol reactivity in this sample. The findings point specifically to the combination of female sex and the subjective severity of childhood trauma.

The authors discuss several biological reasons for these findings. Childhood is a period of high neural plasticity. The brain is developing rapidly and is highly sensitive to environmental inputs. Trauma during this window may embed a predisposition for altered stress responses.

Hormones likely play a mediating role. Estrogen is known to dampen cortisol reactivity. This effect can be protective in healthy individuals, preventing the body from overreacting to minor stressors. However, in women with trauma histories, this natural dampening might combine with trauma-related dysregulation. The result could be a stress response that is too low to be effective.

These findings have implications for how researchers and clinicians approach trauma. The “biological embedding” of childhood trauma appears to manifest differently depending on sex. This challenges the utility of research models that do not separate data by sex.

The results also support the importance of asking patients about their own perceptions of their history. Simply knowing that a person experienced a specific event is not enough. Knowing which event the patient perceives as the most impactful provides greater insight into their physiological status.

There are limitations to this study that affect how the results should be interpreted. The sample size was relatively small. This was particularly true for the male group, which included only 22 participants. A larger sample might reveal patterns in men that were not detected here.

The study also relied on retrospective self-reports. Participants had to recall events and rate their severity from memory. This method can be influenced by a person’s current emotional state. Additionally, the participants were relatively young, with an average age of 25. It is not known if these cortisol patterns persist or change as women enter middle age or menopause.

The study design was cross-sectional rather than longitudinal. This means it captured a snapshot in time. It cannot definitively prove that the childhood trauma caused the blunted cortisol. It only establishes a strong association between the two in women.

Future research is needed to confirm these findings in larger, more diverse groups. The authors suggest that future studies should account for cumulative lifetime stress. Women often carry a higher burden of chronic daily stress, which could also influence hormonal baselines.

Understanding these mechanisms could eventually lead to better treatments. Current therapies for PTSD often involve exposure to traumatic memories. Some research suggests that cortisol helps the brain process and extinguish fear memories.

If women with childhood trauma have low cortisol availability, they might benefit from treatments timed to coincide with their natural daily cortisol peaks. Alternatively, they might be candidates for pharmacological interventions that temporarily boost cortisol during therapy. Unraveling the specific pathways of dysregulation is the first step toward such personalized medicine.

The authors note that despite decades of study, the biological pathways linking trauma and disease remain elusive. Accounting for sex differences offers a promising route to resolving this quandary. By acknowledging that women are not simply “small men,” medical science can move toward more equitable and effective mental health care.

The study, “Not small men: Sex-specific determinants of cortisol reactivity to psychosocial stress following trauma,” was authored by Liza Hinchey, Francesca Pernice, Holly Feen-Calligan, Shannon Chavez-Korell, David Merolla, and Arash Javanbakht.