What Is Military Sexual Trauma (MST)?

Military sexual trauma, or MST, is the term the U.S. Department of Veterans Affairs uses to describe sexual assault or repeated, threatening sexual harassment that occurs during military service. It is not a clinical diagnosis but a label that captures a specific context: unwanted sexual experiences that happen within the unique power structures, close quarters, and rigid hierarchies of the armed forces. A meta-analysis spanning decades of research found that about 16% of military personnel and veterans report MST when the definition includes both harassment and assault, with rates dramatically higher among women (roughly 38%) than men (about 4%).¹ The consequences reach well beyond the initial experience, often shaping mental health, physical health, relationships, and economic stability for years or decades afterward.

How MST Differs from Civilian Sexual Trauma

Sexual assault and harassment happen in civilian life, too. What makes MST distinctive is the environment. Service members live, eat, sleep, and work alongside the people who may have harmed them. Transferring away from a unit is rarely quick or simple, and leaving the job altogether can mean forfeiting a career, benefits, and housing in one stroke. The chain of command often controls both the reporting pathway and day-to-day work assignments, which means reporting an assault can feel like handing your complaint to the same authority that controls your promotion, your schedule, and your reputation.

Research on MST survivors consistently highlights this organizational dimension. One study framed the military’s organizational climate itself as a barrier to seeking help after sexual assault, finding that the culture of unit cohesion and loyalty to the chain of command can discourage women from coming forward.² A policy analysis identified chain-of-command involvement in reporting and prosecution as a central challenge, noting that victims frequently avoid the system out of fear of workplace retaliation.³ That dynamic can compound the psychological damage: the institution you depend on for safety becomes the institution that failed to protect you, or that actively punished you for speaking up.

How Common Is MST

Prevalence estimates vary depending on how the question is asked. When researchers define MST broadly to include both sexual harassment and sexual assault, about 16% of military personnel and veterans report it. When the definition narrows to assault alone, the figure drops to around 14%. When only harassment is measured, roughly 31% report it.¹ A population-based study found that about 44% of female veterans and about 4% of male veterans reported MST.⁴

Those numbers carry a counterintuitive footnote. Because the U.S. military is roughly 85% male, the absolute number of men affected by MST is nearly equal to the number of women, even though a much smaller percentage of men screen positive.⁵ The conversation about MST often centers on women, for understandable reasons, but the raw numbers mean this is very much a problem for men too.

The Mental Health Toll

MST is strongly linked to post-traumatic stress disorder, depression, anxiety, dissociation, and suicidal thoughts. What stands out in the research is that MST often hits harder, psychologically, than other kinds of military trauma. A literature review comparing MST with combat exposure found that while both predicted PTSD symptoms, MST was more closely tied to depression and suicidality, whereas combat exposure was more connected to alcohol use and externalizing behaviors.⁶

Veterans seeking care for MST-related issues tended to show more severe PTSD, depressive, and dissociative symptoms than those seeking care for other military traumas, and were more likely to meet criteria for anxiety disorders and psychotic disorders beyond PTSD alone.⁷ One study of female veterans with PTSD found that those who identified MST as the primary source of their symptoms were at least three times more likely to report current suicidal thoughts compared to those whose PTSD stemmed from combat or deployment.⁸

Part of this heightened impact relates to something researchers call moral injury. In combat, the betrayal element typically involves acts the veteran committed or witnessed. With MST, the betrayal runs in a different direction: the harm came from someone who was supposed to be on your side, in an institution you trusted. A study of post-9/11 veterans found that MST was linked to PTSD and depression specifically through feelings of betrayal, whereas combat trauma operated through a different pathway involving perpetration-related guilt.⁹ A later review reinforced this, concluding that MST may itself be a morally injurious event rooted in betrayal, which could benefit from treatment approaches designed specifically for moral injury.¹⁰

Physical Health and Chronic Pain

The consequences of MST are not confined to mental health. A growing body of research links MST to chronic pain conditions. A large study of female veterans found that women with a history of MST had roughly a quarter higher odds of presenting with any pain condition compared to women without that history, after adjusting for age, weight, smoking, and ethnicity. The association held across a wide range of pain types: irritable bowel syndrome, chronic pelvic pain, back pain, joint pain, fibromyalgia, painful intercourse, abdominal pain, and headaches. The same study found that drug abuse and overdose were also associated with MST history.¹¹

Research with both men and women veterans supports the broader picture: MST may intensify the overall burden of chronic pain, and younger veterans with MST seem to be especially vulnerable to poor outcomes in pain rehabilitation programs.¹² One study parsed the question further, finding that sexual assault was associated with chronic pain but that sexual harassment alone was not, at least as an independent predictor. However, sexual harassment was associated with greater anxiety and depressive symptoms, which themselves feed into pain.¹³ The takeaway is that the health fallout from MST tends to be tangled: mental health symptoms and physical symptoms reinforce each other, and treatment that addresses only one side often falls short.

Substance Use

A positive screen for MST is associated with higher risk for substance use disorders in women veterans, alongside elevated risk for PTSD, depression, and suicidality.¹⁴ Alcohol misuse, in particular, has received attention as a coping mechanism among service members who have experienced combat or MST. Researchers have explored self-medication models, in which drinking becomes a way to manage anxiety, insomnia, and intrusive memories, as well as genetic vulnerability models that might explain why some trauma survivors develop substance problems while others do not.¹⁵ When substance use and PTSD co-occur after MST, each condition makes the other harder to treat, which is one reason integrated treatment programs that address both at once tend to work better than sequential approaches.

Homelessness and Economic Instability

MST can destabilize lives in ways that ripple far beyond the clinic. Among its long-lasting consequences are alcohol and drug problems, depression, chronic health issues, and unstable housing.¹⁶ The link to homelessness has been studied in detail. A large study of veterans found that those who screened positive for MST were more than twice as likely to experience homelessness within five years of leaving the military compared to those who screened negative. Within 30 days, the rate was 1.6% for MST-positive veterans versus 0.7% for those without MST. Within five years, the gap widened to 9.6% versus 4.3%. The association held even after accounting for co-occurring mental health and substance abuse diagnoses.¹⁷

A finding that may surprise readers: after full adjustment, male veterans who screened positive for MST actually faced higher odds of homelessness than female veterans with the same screen result.¹⁷ This could reflect the fact that fewer support resources have historically targeted men with MST, or that the stigma surrounding male sexual victimization discourages men from seeking help before their situation becomes dire.

Male Survivors and the Stigma Problem

Although a greater proportion of women experience MST, the Department of Defense estimates that the absolute numbers of affected men and women are roughly equal across all branches and ranks. Despite this, very little research has focused specifically on how MST affects men.⁵ Social stereotypes about masculinity, persistent myths that men cannot be sexually assaulted, and military culture’s emphasis on toughness all shape how a man interprets what happened to him and whether he seeks treatment. Many male survivors do not label their experience as assault, particularly if no physical force was used or if the perpetrator was also male, which can delay recognition and treatment by years.

The VA disability claims system reflects some of these disparities. An analysis of MST-related PTSD claims found that MST claimants overall had about twice the odds of being denied compared to combat-related PTSD claimants. Within MST claims, men had about 1.8 times higher odds of denial than women, and Black claimants had about 1.4 times higher odds of denial than White claimants.¹⁸ Part of the gap likely stems from documentation challenges: MST often lacks the kind of service records that combat PTSD claims can draw on, and men may have even less corroborating documentation because they reported less frequently at the time.

LGBTQ+ Service Members Face Higher Rates

Research on sexual minority service members paints a stark picture. A descriptive study of LGBT military personnel found high rates of both sexual harassment and sexual assault across genders, with women more likely than men to report harassment.¹⁹ A separate study using multivariable models found that LGB identity was a significant predictor of sexual harassment, stalking, and sexual assault. LGB service members had roughly four times the odds of experiencing sexual harassment and about twice the odds of experiencing assault compared to non-LGB peers. An interaction between LGB identity and sex suggested that male LGB service members, specifically, faced elevated harassment risk relative to their heterosexual male counterparts.²⁰

These findings reinforce a broader pattern: MST does not affect everyone equally. It concentrates among people who already occupy less powerful positions within military hierarchies, whether because of gender, sexual orientation, rank, or race. Understanding that pattern matters for designing prevention programs that address the structural conditions, not just individual behavior.

VA Screening and Treatment

Since the late 1990s, the VA has implemented universal MST screening for all veterans who seek VA healthcare. Every veteran is asked whether they experienced sexual assault or repeated threatening sexual harassment during military service. The screening is brief and designed to open a door rather than to diagnose. An evaluation of the screening program found that a positive screen was associated with a more than twofold increase in subsequent mental health treatment among veterans who had not previously used mental health services. For women, about one in every six positive screens led to a new patient accessing treatment; for men, about one in every seven.²¹ The screening program is widely regarded as one of the VA’s genuine successes in connecting trauma survivors to care.

As for what that care looks like, the VA offers MST-related treatment at no cost, regardless of whether the veteran has service-connected disability or even VA enrollment for other healthcare. The evidence-based therapies most commonly used for MST-related PTSD are cognitive processing therapy and prolonged exposure therapy. A study examining both treatments found that MST history, regardless of the veteran’s gender, did not worsen PTSD outcomes in either therapy. Both treatments were effective for veterans with and without MST.²² That finding is reassuring, though it does not mean recovery is easy or quick. Many veterans with MST have complex presentations involving PTSD, depression, chronic pain, and substance use simultaneously, and treatment planning needs to account for all of them.

Filing a VA Disability Claim for MST

Veterans who develop PTSD or other conditions as a result of MST can file for VA disability compensation. The process, however, is harder than for many other service-connected conditions. Combat trauma claims can often point to deployment records, combat action ribbons, or unit logs. MST claims frequently lack this kind of documentation, especially when the assault was never reported. The VA has special evidentiary rules for MST claims, allowing “markers” like a sudden request for transfer, changes in work performance, unexplained visits to sick call, or evidence of relationship breakdown around the time of the alleged trauma. Even so, denial rates are higher for MST-related PTSD claims than for combat-related PTSD claims, with MST claimants facing roughly twice the odds of denial.¹⁸

Veterans filing MST-related claims are often advised to gather any supporting evidence they can: buddy statements from fellow service members, personal journals, letters or emails from the relevant time period, records of counseling with a chaplain or social worker, or documentation of behavioral changes. The VA also has MST coordinators at every facility who can help navigate the claims process. Veterans service organizations like the DAV, VFW, and American Legion provide free claims assistance and are familiar with the particular evidentiary challenges MST survivors face.

The Problem Is Not Only American

MST is most extensively studied in the United States, partly because the VA’s screening program produces large datasets and partly because U.S. military sexual assault has received sustained media and congressional attention. But the problem is not unique to the American armed forces. A review of the UK military justice system characterized the British military as a hypermasculine culture that is seemingly permissive of sexual violence, with high prevalence of sexual offenses and low conviction rates. Victim-survivors reported poor treatment within the service justice system. Reformers recommended that rape cases be tried in civilian courts, though the Ministry of Defence ultimately rejected that recommendation in 2021 and committed instead to internal reform.²³ Similar debates about whether military justice systems can fairly handle sexual offenses have played out in Canada, Australia, and several other countries with volunteer militaries.

In the U.S., recent legislative changes have moved prosecution of sexual assault cases outside the chain of command for the first time, placing them instead under independent special trial counsel. Whether these reforms actually reduce MST rates or improve survivors’ experiences with the justice system remains to be seen, but the structural critique that drove them is well supported: when the same authority structure that failed to prevent the assault also controls its prosecution, survivors face a system that can feel rigged against them from the start.