American Scientist

When an issue arises with a person’s menstrual health, it is often framed as an individual problem. Maybe one’s period is early or late, short or long, heavy or light, especially painful, or somehow “abnormal.” But as anthropologist Kate Clancy points out in her inaugural book Period: The Real Story of Menstruation—a welcome outgrowth of her Period Podcast—the whole idea of a normal period is a myth, one begotten from eugenics that continues to pervade medical practice and menstruators’ perceptions of ourselves. Problems with our periods are often met with a confusing cloud of nonsolutions or half solutions, which can be isolating, especially because we live in cultures where we are expected to pass as not menstruating, at all times. Clancy builds the case that these problems are far from individual. (See Clancy’s feature, “How Endocrine Disruptors Affect Menstruation,” September–October 2021.)

“Our culture, our environment, the ways in which our various identities are targeted for harm, and our lived experiences shape menstruation,” writes Clancy. The ideal of “Norma,” an almost laughably named actual statue meant to represent the “statistically average” woman unveiled at the American Museum of Natural History in 1945 (along with the male version, Normman), is used as an extended metaphor in the book. The statue’s physique was based on a sample of tens of thousands of white American women in their early adulthood. (These names read like satire, but they were not intended as such). Norma and her compadre were the result of a scientist-artist collaboration between the gynecologist Robert L. Dickinson and sculptor Abram Belskie.

The concept of an idealized normal woman like Norma, Clancy says, “comes straight from eugenic science, and it is a misplaced belief that those who occupy the averages are healthy, and those on the margins are flawed.” A “normal” period has been conflated with a healthy period in much of the scientific literature on menstruation.

“Normative femininity has influenced our understanding of the menstrual cycle in two ways: it has created the idea that the menstrual cycle and its related processes are passive and nurturing, and it has encouraged physicians and patients to feel the need to regulate abnormal cycles toward a normal shape and length,” writes Clancy. “The normal menstrual cycle, constrained by normative femininity, barely resembles the reality of what is going on in our uteruses, ovaries, and other organs and systems.” That reality is fascinating and beautiful and profoundly understudied. Clancy highlights research that shows how flexible and variable the process of menstruation is, even in the face of stressors.

To understand how we got to the unfortunate situation of an understudied and widely misunderstood process that half the population experiences with regularity, Clancy begins the book with a history and anthropology lesson. Many cultures view menstruation as sacred, but early (and often male) anthropologists mistook such views as “taboos,” a word that comes from a mistranslated Indigenous Polynesian term, “tabu” or “tapu,” used to describe something with such awe-inspiring power that it commanded “respect and separateness.” The limited interpretation of Western colonists and anthropologists was that this word meant “restrictions and prohibitions.” Indeed, in Western society it is taboo (as in socially restricted) to talk about menstruation. Historians trace this taboo to origins in the medieval period, as capitalism and the Catholic Church came together to “redefine women as having a reproductive value rather than an economic value.”

These cultural forces stuck. Clancy points to their influence on hypotheses about why women menstruate. The earliest one in the 1920s claimed menstrual fluids were toxic, later ones in the 1990s posited that menstruation purges something from the body (abnormal embryos, pathogens from semen) or that menstruation results from the energetic costs of maintaining the endometrium, and a contemporary one suggests that menstruation is useless, along for the evolutionary ride.

A new generation of scientists has now put forward the idea that menstruation prepares the endometrium for later pregnancy. Clancy covers some solid support for this hypothesis, but also cautions against the search for one right answer. “Much of our culture, including the origins of Western science, promotes and rewards hierarchies of knowledge,” writes Clancy. “Maybe there just isn’t a hierarchy.”

Although Clancy writes that separating anthropology from eugenics is “about as easy as unscrambling eggs,” her lab is offering an example of how to make progress. Throughout the book, Clancy highlights how she and other researchers are searching for different ways of doing science, acknowledging the variation that a constant focus on what’s average has ignored. For example, Clancy and her team mapped out the rise and fall of estrogen in Polish and Polish American women. They found three main patterns, and the one most often shown as the norm in textbooks included the smallest number of people. Given our ingrained proclivities to generalize to some sort of Norma, Clancy is quick to point out: “The central idea here is not that there was one Norma and now there are three; it’s that there are a wide variety of definable patterns that are likely to be sample and even population-specific.”

Clancy spends the middle of the book looking at the systemic, societal forces that affect menstrual health and our perceptions of it. It’s educational and infuriating—and perhaps most especially so because so few of the people who need to know this information do know it. Stereotypes that women are fragile, that we should look thin, that we are overly emotional or hysterical, and that our fertility is valued above all else have led to unsupported ideas that intense exercise is bad for periods, that our pain isn’t real or is exaggerated, and that undereating is less risky than being overweight (a word that has normal/Norma baked right into it). “Ovarian function can and does anticipate quite a bit of energy expenditure without any lasting or harmful effects, and it protects and prioritizes itself over any other beings for which it might be responsible,” writes Clancy. “As a result, the body frequently deprioritizes the menstrual cycle in a way that is flexible and adaptive, that leads to a range of experiences, and that allows it to spring back as conditions and desires allow.” Clancy points to societal factors such as sexism, racism, and fat stigma as influences on menstrual health and the care people with periods receive.

When it comes to menstruation, medicine puts a myopic focus on fertility (either preventing unwanted pregnancies or maintaining fertility above all else), ignoring other concerns that people with uteruses may have. Clancy uses the emphasis on putting menstruators on contraceptive methods as a case in point. Studies show that about half of people prescribed hormonal contraceptive methods discontinue them, and rates of discontinuation are similarly high for intrauterine devices (IUDs). Among those who do continue to use these methods, complaints about unwanted side effects are not uncommon. “The overfocus on how successful a product is in preventing birth, over side effects or one’s ability to stop or start the product at will, is how physicians are taught to recommend contraceptive options,” Clancy writes. “This limits patients’ abilities to generate their own priorities to inform their choices.” Although these contraceptive methods are often framed as important to women’s choice—which is quite consequential at a time when access to abortion is increasingly threatened and restricted—a look at the details of patient-doctor interactions shows a more complex set of experiences, intersecting with sexuality, gender identity, race, disability, age, and socioeconomic status. Clancy is careful to acknowledge this need for access to safe and effective contraception and menstrual suppression, while also pointing out that options that are discontinued by half of those who try them fall far short of these ideals of women’s empowerment. “There are no methods being tested right now that do not require hormonal manipulation in order to reversibly suppress the period,” Clancy notes. “I cannot imagine such a low level of research and development were these products that primarily affected cisgender men.”

Clancy also uses the COVID-19 vaccine trials as a case to point out how much menstrual health is ignored by today’s medical community. When people with uteruses repeatedly claimed that the vaccines affected their periods, with some reporting heavy or breakthrough bleeding, the scientific community mostly did not listen, which encouraged unfounded fears and conspiracy theories that deterred people from getting the vaccine. The only data on menstruation that is standard to gather in vaccine trials, including the vaccines for COVID-19, is the last date of the menstrual period, which is used to screen out participants who are pregnant. Participants are then followed for only a week after the vaccine is administered, often before a lot of participants menstruate.

Clancy’s lab stepped in to gather data retroactively, surveying people with periods about their experiences with the vaccines and confirming the salience of experiences with heavy or breakthrough bleeding. By listening to people’s experiences, Clancy then had the platform for affirming the vaccines’ safety, explaining that these short-term effects on people’s periods made sense in light of the higher inflammation that can occur as a newly vaccinated person’s immune system ramps up.

After covering the effects of stressors such as exercise or inflammation brought on by the immune system, Clancy turns her attention to psychosocial stressors. “Many associational studies have found that measures of psychosocial stress, past and present, are higher among people with menstrual pain, irregular cycles, and even amenorrhea,” Clancy writes. Menstruators living in Western countries tend to report worse menstrual symptoms than those in many other cultures. Clancy notes that people in Western societies “have… developed a tendency to describe menstruation almost entirely with negative symptomology.” Ethnic minority women living in the United States experience higher rates of premenstrual dysphoric disorder (PMDD) than those in other countries, and their risk for it increases the longer they have lived here. Another study showed that women who reported experiencing discrimination were more likely to have PMDD and premenstrual symptoms in general. People who have experienced physical abuse or sexual abuse also show varying menstrual experiences, including the timing of PMDD (if they experience it). It’s important to point out that PMDD is an umbrella term that covers “psychological, somatic, behavioral, and emotional symptoms,” and that the timing of PMDD symptoms falls into several categories, indicating a mixed etiology. In offering these examples, Clancy is making a point about the systems that lead to better or worse sexual health, but she is careful to caution that “these population-level correlations are… highly unlikely to have a direct causal pathway.” Psychosocial stressors do not simply affect menstruation the way that other stressors do, and they may affect different categories of PMDD sufferers in distinct ways.

In the final section of the book, Clancy turns to science fiction, from Enlightenment-era Frankenstein by Mary Shelley to speculative works from fourth-wave feminist writers, to imagine a better future. “Menstrual liberation is about becoming more visible as menstruating people while working to ensure that our needs are considered alongside our community’s and planet’s needs,” writes Clancy. In the future Clancy imagines, menstruation would be more visible, better networks of care would exist so that people with periods could take care of themselves and those around them, funding institutions would devote the proper resources to study menstruation, better technologies for contraception would exist, and there would be a cure for endometriosis and other vastly underfunded and overlooked problems with menstrual health.

Over and over again, Clancy shows that “the solution to negative menstrual experiences requires communities of care and structural change, rather than an individualist approach in which each menstruating person tries to handle their symptoms or fertility struggles on their own.” That is, indeed, what sets her book apart. Many of the books on menstrual and pelvic health that I’ve read over the years have been helpful and compelling, but all of them tend to offer individualistic solutions. Clancy shows that that approach only gets us so far. Ultimately, what people with or who once had periods need is structural change. “What I want for you more than anything is to abandon the idea that you are wholly responsible for your menstrual health and that changes to your menstrual health are your problem and yours alone,” Clancy writes. Period is a step toward creating that structural change. Reading it has made me feel less alone, pointing me to the people with whom I can begin to cocreate that future.