PMDD affects around 5% of menstruating people of childbearing age, though some researchers believe this is a conservative estimate. PMDD occurs in the luteal phase of the menstrual cycle between ovulation and the start of a period. Characterized by a combination of up to eleven symptoms, including extreme irritability, suicidal thoughts, insomnia, and tachycardia, PMDD entered the Diagnostic and Statistical Manual of Mental Disorders in 2013, making it a fairly recent addition. Researchers remain unclear about the causes of PMDD, but some believe it stems from a precipitous drop in serotonin as hormones fluctuate—an atypical response to typical physiology.
The DSM is curious place to catalogue an illness triggered by something physical. “When PMDD originally hit the scene, some feminists were angry,” Caldwell says, drawing on her treasure trove of research, which includes the history of sanitary products, the differences between cycle-tracking apps, and Reddit thread gems. “Some feminist psychologists believed that the language surrounding PMDD is misleading and that its classification as a psychiatric disorder stigmatizes women as mentally ill and covers up the real reasons for women’s anguish.”
Caldwell doesn’t disagree. She acknowledges that periods come loaded with “time of the month” stereotypes that infantilize and dismiss women. But she ultimately feels grateful for a diagnosis: “Now that I had a name for what I was feeling, I was certain I’d be able to control the outbursts with my mind.”
But treating PMDD as an aberration and therefore governable—Caldwell writes letters to herself during non-PMDD weeks to read during PMDD episodes, and she and Tony come up with strategies, such as putting their phones in “airplane mode” to avoid fighting via text—proves difficult and stressful, even as Tony insists Caldwell not judge their relationship based on “two bad days a month.” After trying antidepressants, supplements, dietary changes, and other methods recommended by doctors, her therapist, and fellow PMDD-Redditors, and even attending a PMDD conference, Caldwell realizes that her menstrual cycle, like the cycles of all menstruating people, will never be fully sublimated. More importantly, menstruation cannot be isolated from the rest of Caldwell’s life and the people in it who love her. Periods create, in fact, the very cycle of her life. They are its primal plot.
The Red Zone thrives when Caldwell gets deeply curious about something she and half the world’s population experience. Millions of periods must be starting as I type this, and yet it’s this very ubiquity that makes a period both the butt of sitcom jokes and a phenomenon mysterious enough that doctors still don’t know what causes PMDD. “We were never told what a ‘regular’ period should look like,” Caldwell writes. “At least in my middle school or high school, we were never handed three buckets of blood and told which one was light, regular, and heavy.”