Premenstrual syndrome (PMS) is often a convenient butt of jokes — a handy way to dismiss emotional expression as a transient byproduct of biology. However, for the 8 to 20 percent of reproductive-age people who get periods, PMS and its more extreme case, premenstrual dysphoric disorder (PMDD), are not funny at all, but a life-altering set of symptoms that wreak emotional and physical havoc. PMS and PMDD both show up during the luteal phase of the menstrual cycle, which begins just after ovulation and can last up to 14 days. PMDD is like PMS on steroids.

Symptoms can include hypersensitivity to stimuli and pain, pelvic pain or cramping, and bloating. Where PMDD differs is in the intensity of mood symptoms, which are generally more severe and recurrent and interfere with a person’s ability to work, socialize, and have healthy relationships. Studies have shown that women with PMDD have diminished positive emotional processing, depression, and anxiety and are at an increased risk for postpartum depression and suicidal behavior. One study even estimated that the average costs of PMDD run about $4,300 per year in lost wages or additional health services.

Though the field of hormone sensitivity research is relatively young, one consistent link that repeatedly turns up is that women with PMDD have higher incidences of past physical and emotional abuse.

For almost two weeks out of every month, Mary Barnes (not her real name), a 43-year-old woman from Minnesota, must plan for her PMDD symptoms, which can come on like bad weather at the start of her luteal phase. These symptoms can include cramping that seizes her entire abdomen and interferes with basic elimination. “It often hurts to pee,” says Barnes, as her reproductive and digestive systems “clamp down” and become inflamed. “We schedule our vacations around the two weeks that I feel myself.” During her PMDD episodes, Barnes will slide into a deep depression in a matter of minutes, and her mind fills with “very existential, creepy questions,” such as “are my kids going to die today?” It’s a “very paranoid, hopeless feeling,” coupled with panic attacks and a “general sense of wired unease.” Barnes and her husband plan for evenings on the couch, easy meals, and going to bed early during these times.

Though she was formally diagnosed with PMDD by both a psychiatrist and a gynecologist, after 20 years of seeking help for it through Western medicine, Barnes found herself frustrated by a lack of resources from medical professionals, who rarely took her symptoms seriously. She turned to alternative medicine for her problems, including supplements such as St. John’s wort and Sam-e, massage, chiropractic, a therapist, and most recently a pelvic floor therapist. In addition, Barnes read numerous books about “non-Western” perspectives on women’s health. “I have learned that we hold memories in our bodies; our muscles and tissues remember the pain that was inflicted.”

Barnes experienced physical and emotional abuse by her brother from an early age: “The physical abuse left marks on my skin.” Her brother engaged in such torments as squishing her between bean bags and sitting on her until she hyperventilated from lack of air and terror. “He would hold me down and tickle me until I urinated on myself.” Begging him to stop only made it worse: “He got off on my fear.”

She also suffered physical and sexual abuse at the hands of her high school boyfriend, a national champion wrestler and valedictorian, who raped her, which caused an ovarian cyst to burst and cause scar tissue: “I still can’t find the words to describe the pain,” says Barnes. “Guess who people believed?”

Trauma is in and of itself a well-researched precursor to multiple other mental and physical health disorders, so it’s not surprising to experts in the field that it’s linked to PMDD. “It’s really astounding how many disorders are predicted by trauma,” says Tory Eisenlohr-Moul, a clinical psychologist and incoming associate director of translational research in the women’s mental health research program at the University of Illinois, Chicago.

Trauma causes changes in the hypothalamic-pituitary-adrenal (HPA) axis, a stress-responsive system that enables us to adapt to environmental challenges and stressors, explains Eisenlohr-Moul. “The ultimate byproduct of the HPA axis is cortisol, a hormone that mobilizes energy resources in order to respond to stressful events and to meet the energy demands of life.”

In her research on women with trauma and PMDD, Eisenlohr-Moul has most commonly found a blunting of the stress response—that is, a flat line or small increase in cortisol after a stressful situation—whereas people without trauma have a significant increase. These women also appear to have increased sensitivity to their ovarian steroid hormones during the luteal phase, which seems to dysregulate that HPA axis, altering thyroid function, increasing pain sensitivity, and impairing sympathetic nervous system function.

This may explain why PMDD/PMS share traits in common with post-traumatic stress disorder (PTSD), something war veterans and first responders often experience.

Where it gets sticky is attempting to understand why this association exists. There is research suggesting that those with the estrogen alpha receptor (ESR1) gene have a higher risk of PMDD, but this field of research is relatively new. “We don’t know a lot about whether trauma is causing hormone sensitivity, or whether it’s just that trauma is so common in women that…they tend to have more symptoms because they have more underlying mental health symptoms anyway, and it amplifies the expression of their hormone sensitivity,” says Eisenlohr-Moul.

A 2016 study in Psychoneuroendocrinology looks at this association between past abuse and PMDD. Though not a direct cause, the researchers found that “history of physical abuse unmasked a positive association between cyclical increases in P4 [progesterone] and mood symptoms.”

However, this research opens more questions than it answers. Eisenlohr-Moul admits that they simply haven’t studied the subject comprehensively enough to know why. “I wonder if maybe things like duration of abuse or timing of abuse [are responsible]. Did it happen during a critical brain development period? Maybe the physical abuse is more likely to be chronic.”

There are also studies linking dysregulation of the serotonin and allopregnanolone systems, for which doctors often prescribe SSRI drugs, but these don’t work for every woman. Barnes had “a horrible reaction” to Serafem, a form of Prozac.

Eisenlohr-Moul and others in her field are careful to clarify that underlying mental health issues and their effects on PMDD symptoms do not suggest that PMDD symptoms are only in the sufferer’s head. She feels that medicine generally “focuses on fixing the biology, and they don’t zoom out and look at the context in which it happened. [Trauma] is a situation where prevention would truly be worth a lot more. We know that trauma influences mental health.”

Laura Kiesel of Massachusetts, who has PMDD and a history of past abuse, is unsure that therapeutic interventions would have made any difference in her life unless they’d come early enough to stop her childhood abuse. “I think once the markers of abuse and trauma take hold, they quickly become a part of one’s biology and can be very difficult to undo,” she says.

Kiesel was spanked as a very young child by her stepfather, “often for being afraid of the dark and not sleeping well.” She had welts and bruises on her butt so severe that she couldn’t sit during preschool classes. Her mother was also prone to occasional violence under the influence of drugs. “She smacked me hard enough to leave handprints on my face for hours and once split my lip open with a backhand.”

Kiesel has struggled for years with PMDD and other health issues, including endometriosis. Her emotional flare-ups can get so bad that they have “contributed to or worsened arguments” with her partner: “I am quick to anger and rage and have crying jags to the point where I feel a bit of a loss of emotional control compared to other times of the month.”

But Barnes, who has recently begun working with a therapist, feels therapy has made a difference. “I need a therapist to feel safe. She’s given me permission to feel pain in my body and know it’s not going to last,” says Barnes.

Not all women with PMDD will experience relief from talk therapy, particularly those prone to suicidal ideation, says Eisenlohr-Moul. “It’s a really tall order to ask people who are suffering and experiencing that much mood flux to fix it all with skills.”

For some women, hormone intervention and even hysterectomy may be necessary, but it’s very important that women avoid overdiagnosing their hormone sensitivities, says Eisenlohr-Moul. “It doesn’t mean your symptoms aren’t real. It just means that maybe you should seek different avenues of treatment that aren’t focused on hormones.” She recommends keeping a daily journal to chart symptoms for an entire month to see whether they appear to be confined to the luteal phase or persist beyond it.

Awareness of this link would have saved Barnes years of frustration in her journey to better health. “If I had known sooner that my past abuse could have been affecting my health,” she says, “I would have sought out alternative therapies much sooner than I did.”

For more information on treatment recommendations, here are guidelines by the Royal College of Gynecologists and Obstetricians (the U.S. guidelines are currently under revision). Check out the Gia Allemande Foundation, a nonprofit focusing on the prevention, treatment, and research of PMDD.