Elissa Stein and Susan Kim – Flow: Book Review & Audio Summary

Book Info

• Book name: Flow: The Cultural Story of Menstruation
• Author: Elissa Stein, Susan Kim
• Genre: Social Sciences & Humanities, Health & Wellness
• Pages: 272
• Published Year: 2009
• Publisher: St. Martin’s Griffin
• Language: English

Audio Summary

Synopsis

Flow takes readers on a fascinating journey through the cultural history of menstruation, revealing how this natural bodily function has been shrouded in shame and misunderstanding for centuries. Authors Elissa Stein and Susan Kim unpack the myths, taboos, and medical misconceptions that have shaped women’s experiences with their periods from ancient times to the present day. Through compelling historical research and modern scientific insights, they explore everything from menstrual huts and bloodletting to PMS and period sex. This groundbreaking book challenges readers to reconsider what they think they know about menstruation and empowers women to make informed decisions about their bodies. It’s an essential read for anyone seeking to understand the intersection of biology, culture, and women’s health.

Key Takeaways

• Menstruation has been misunderstood and stigmatized throughout history, with ancient myths portraying period blood as both sacred and toxic, leading to women’s exclusion from religious and social institutions.
• What we now call PMS was historically diagnosed as “hysteria,” revealing centuries of medical ignorance about female anatomy and the ongoing lack of comprehensive research into menstrual health.
• Period sex, while culturally taboo in many societies, is medically safe and normal—the stigma stems from religious and cultural beliefs rather than scientific evidence.
• Despite having approximately 450 periods in a lifetime, many women lack basic knowledge about menstruation due to persistent shame and inadequate education about female sexual health.
• Understanding the historical context of period taboos helps us challenge contemporary stigmas and make more informed, empowered choices about our bodies.

My Summary

Why We Need to Talk About Periods

I’ll be honest—when I first picked up Flow by Elissa Stein and Susan Kim, I wasn’t sure what to expect. As someone who’s spent years reading and reviewing books, I’ve noticed that topics related to women’s health often get sidelined or treated with kid gloves. But this book? It dives headfirst into one of the most universal yet least discussed aspects of being a woman: menstruation.

The statistic that hit me right away is this: women have about 450 periods during their lifetime. That’s roughly 38 years of monthly cycles, yet so many of us—myself included—have grown up with minimal understanding of what’s actually happening in our bodies. The shame and embarrassment surrounding periods have created a knowledge gap that affects not just individual women, but entire generations.

What Stein and Kim accomplish in Flow is nothing short of revolutionary. They’ve created a comprehensive cultural history that traces how menstruation has been perceived, misunderstood, and weaponized against women throughout human history. More importantly, they provide the scientific facts we should have learned long ago, presented in an accessible, engaging way that makes you wonder why this information isn’t standard curriculum in every school.

The Ancient Roots of Period Shame

One of the most eye-opening sections of the book explores how ancient civilizations viewed menstruation. The authors reveal a fascinating paradox: period blood was simultaneously considered sacred and toxic. On one hand, it was seen as the sacred remains of an unborn child—a substance connected to the miracle of life itself. On the other hand, it was condemned as dangerous and evil.

The Roman philosopher Pliny the Elder wrote in his book Natural History (77 AD) that period blood could cause horses to miscarry and flowers to die. Think about that for a moment—these weren’t fringe beliefs held by a few superstitious individuals. These were “scientific” assertions made by one of the most respected intellectuals of his time, and they went unchallenged for over a thousand years.

What struck me most was learning that some of these beliefs persisted well into the 20th century. Even today, certain cultures maintain these toxic myths about menstruation. The authors document how women in some parts of the world are still sent to menstrual huts during their periods, isolated from their communities as if they’re contagious.

This historical context helps explain why so many modern women still feel embarrassed about their periods. We’re not just fighting against our own internalized shame—we’re pushing back against thousands of years of cultural conditioning that told women their natural bodily functions made them inferior, dangerous, or unclean.

Bloodletting and Medical Misunderstanding

The book’s exploration of bloodletting particularly fascinated me. Based on the belief that menstruation was the body’s way of purging toxic blood, doctors developed this procedure to treat various illnesses in both men and women. But here’s the kicker: because menstruation was uniquely feminine, the myths surrounding it were specifically used to justify women’s subordinate position in society.

If your body naturally produces “toxic” blood every month, the logic went, then clearly you’re inferior to men who don’t experience this “problem.” It’s a perfect example of how medical misunderstanding can be weaponized to maintain power structures. The authors do an excellent job of connecting these historical dots, showing how ancient superstitions evolved into pseudo-scientific justifications for gender inequality.

From Hysteria to PMS: How Little Has Changed

Perhaps the most infuriating chapter in Flow deals with the evolution from “hysteria” to PMS. During the Middle Ages, women exhibiting symptoms like insomnia, mood swings, or random bursts of emotion were accused of being witches. The diagnosis of hysteria encompassed all of these symptoms and more.

Even Hippocrates, the father of medicine himself, believed that hysteria was caused by the uterus moving around inside a woman’s body. Yes, you read that right—the uterus was thought to be some kind of internal snake, slithering through the body and causing problems. It sounds absurd now, but this was accepted medical knowledge for centuries.

The treatments for hysteria were equally problematic. Stein and Kim detail everything from using leeches on patients’ vulvas to X-ray treatments. The most common treatment involved doctors or midwives stimulating the patient’s clitoris until orgasm. While this was viewed as a legitimate medical procedure (and not something to be performed at home), it reveals the profound ignorance about female sexuality and anatomy that persisted for millennia.

The Modern Mystery of PMS

Here’s what really got me: the American Psychiatric Association didn’t drop the diagnosis of hysteria until 1952. That’s within living memory for many people. Just one year later, the diagnosis of premenstrual syndrome emerged to replace it.

But here’s the uncomfortable truth that Flow highlights: we don’t really understand PMS much better than our ancestors understood hysteria. Sure, we know that cramps result from uterine contractions, but there’s no conclusive evidence about what causes other symptoms like mood swings or insomnia. In fact, there’s no definitive proof that PMS is even hormonal.

The authors point out that PMS and its more severe form, PMDD (Premenstrual Dysphoric Disorder), are largely Western medical concepts. This raises a provocative question that stuck with me long after finishing the book: Should emotional and physiological reactions during menstruation be treated as problems requiring medical intervention, or are they simply part of the human experience?

I don’t think Stein and Kim are suggesting we ignore genuine suffering or medical conditions. Rather, they’re asking us to consider whether we’ve simply repackaged old prejudices about menstruation in modern medical language. It’s a nuanced argument that challenges both the dismissal of women’s symptoms and the over-medicalization of normal bodily functions.

Breaking the Ultimate Taboo: Period Sex

If talking about periods in general is taboo, then discussing period sex is the taboo within the taboo. This is where Flow really shines in its willingness to address topics that many books would avoid. The authors make a simple but powerful point: modern science has found no evidence that period sex is harmful, yet it remains one of the most stigmatized aspects of menstruation.

The religious roots of this taboo run deep. In Orthodox Judaism, women are considered “nidah” (unclean) for two weeks covering and following their period. During these 14 days, married couples aren’t allowed any physical contact whatsoever—not just sex, but any touching at all. After seven days without any trace of blood, women must bathe in a ritual bath called a mikvah before physical intimacy can resume.

Similar prohibitions exist in many other religious traditions. The common thread is the belief that menstruation makes women contaminated or impure, and that this contamination can be transferred through sexual contact. But as Stein and Kim emphasize, these are cultural and religious beliefs, not medical facts.

Reclaiming Agency Over Our Bodies

What I appreciate about the authors’ approach is that they’re not telling anyone what they should or shouldn’t do. Instead, they’re providing information so women can make informed choices. If someone chooses not to have sex during their period for personal preference, that’s entirely valid. But that choice should be based on personal comfort, not shame or misinformation.

The discussion of period sex also opens up broader conversations about bodily autonomy and sexual agency. For too long, women’s sexuality has been defined by religious doctrine, cultural expectations, and male perspectives. Flow encourages readers to question these inherited beliefs and decide for themselves what feels right.

Practical Applications for Modern Life

Beyond its historical and cultural analysis, Flow offers practical insights that can change how we navigate menstruation in our daily lives. Here are some key applications I took away from the book:

Education and Communication

The first step in breaking down period stigma is education. If you have daughters, nieces, or young women in your life, this book provides a framework for having honest, shame-free conversations about menstruation. Instead of treating periods as something embarrassing or secret, we can present them as a normal biological process worthy of understanding.

I’ve started thinking about how the silence around menstruation in my own upbringing affected my relationship with my body. By being more open in our conversations—whether with family, friends, or partners—we can help create a culture where women don’t feel the need to hide their periods or apologize for their bodies’ natural functions.

Challenging Workplace and Social Norms

The book’s historical examples of women being excluded from churches, workplaces, and social spaces during menstruation aren’t just ancient history. Even today, many workplaces lack adequate bathroom facilities or policies that accommodate menstruation. Some women still feel they need to hide tampons or pads when walking to the bathroom, as if they’re doing something shameful.

Armed with the knowledge from Flow, we can advocate for better workplace policies, from providing free menstrual products in bathrooms to normalizing conversations about period-related health issues. This isn’t about special treatment—it’s about recognizing that half the population experiences menstruation and our institutions should reflect that reality.

Medical Advocacy

One of the most valuable lessons from Flow is the importance of being an informed patient. The book’s documentation of medical ignorance about menstruation throughout history should empower us to ask questions and push back when our concerns are dismissed.

If you’re experiencing severe period pain, irregular cycles, or other symptoms that interfere with your quality of life, you deserve medical attention and answers. Don’t let doctors brush off your concerns as “just PMS” or “normal period stuff.” The lack of research into menstrual health that Stein and Kim highlight means we need to be our own advocates, insisting on thorough investigation of our symptoms.

Rethinking Product Marketing

The book made me more aware of how menstrual product marketing perpetuates shame. Advertisements often focus on discretion, with euphemisms and blue liquid instead of red. They promise that their products will help you hide your period, as if menstruation is something that needs concealing.

By recognizing these marketing tactics for what they are—strategies that profit from our shame—we can make more conscious choices about the products we buy and the messages we support. Some newer menstrual product companies are taking a different approach, using realistic imagery and straightforward language. Supporting these companies sends a message that we’re ready for honest conversations about periods.

Personal Body Literacy

Perhaps the most important practical application is developing what I’d call “body literacy”—really understanding your own menstrual cycle and what’s normal for you. Flow encourages readers to pay attention to their bodies without judgment, tracking patterns and changes not out of anxiety but out of genuine curiosity and self-knowledge.

This means knowing your typical cycle length, recognizing your own premenstrual patterns, and understanding what symptoms warrant medical attention versus what’s normal variation. It’s about moving from shame and ignorance to knowledge and empowerment.

Strengths and Limitations

Flow excels in its comprehensive historical approach and accessible writing style. Stein and Kim have clearly done extensive research, yet they present their findings in a conversational, engaging manner that never feels academic or dry. The book successfully balances scholarly rigor with readability, making it accessible to a wide audience.

The cultural analysis is particularly strong, connecting historical attitudes about menstruation to contemporary stigmas in ways that feel revelatory. The authors don’t shy away from uncomfortable truths, whether discussing religious prohibitions or medical malpractice. This honesty is refreshing and necessary.

However, the book does have some limitations. While it touches on how menstruation is viewed in various cultures, the perspective is primarily Western. A more global approach would strengthen the analysis, particularly given that menstrual stigma manifests differently across cultures.

Additionally, the book was published in 2009, and while the historical content remains relevant, some of the contemporary discussions about menstrual products and activism have evolved significantly. The menstrual equity movement has gained considerable momentum in recent years, with new developments in product innovation, policy changes, and public discourse that aren’t reflected in the book.

The scientific explanations, while helpful, are sometimes limited by the lack of research in this area—which is actually one of the book’s key points. Readers looking for definitive medical answers about issues like PMS may be frustrated by the acknowledgment of how much we still don’t know. However, I’d argue this honesty is actually a strength, even if it doesn’t provide the clear-cut answers we might hope for.

How Flow Compares to Other Books

In the landscape of books about women’s health and menstruation, Flow occupies a unique space. Unlike purely medical texts that focus solely on the biological aspects of menstruation, or feminist manifestos that emphasize only the political dimensions, Stein and Kim’s book integrates history, culture, medicine, and social commentary.

Books like “Period Power” by Maisie Hill or “The Fifth Vital Sign” by Lisa Hendrickson Jack offer more detailed medical and hormonal information, making them excellent companions to Flow. Where those books dive deep into the science of menstrual cycles and hormonal health, Flow provides the cultural context that helps us understand why that information has been hidden from us for so long.

Similarly, “Periods Gone Public” by Jennifer Weiss-Wolf focuses specifically on menstrual equity and policy, taking the conversation in a more activist direction. Flow lays the groundwork for understanding why such activism is necessary by documenting the historical oppression and stigmatization of menstruation.

What sets Flow apart is its accessibility and its role as a comprehensive introduction to thinking critically about menstruation. It’s the book I wish I’d read as a teenager, the one I’d recommend to anyone—regardless of gender—who wants to understand the cultural forces that have shaped attitudes about periods.

Questions Worth Pondering

Flow left me with several questions that I’m still mulling over, and I think these are worth sharing because they get at the heart of what makes this book so thought-provoking:

How would our society be different if menstruation had never been stigmatized? It’s almost impossible to imagine, given how deeply embedded period shame is in our culture. But what if, from the beginning, menstruation had been treated as unremarkable as any other bodily function? How might that have changed the trajectory of gender equality?

And here’s another one: Are we making progress in destigmatizing periods, or are we just finding new ways to package old taboos? Yes, we can now see menstrual product ads on TV and find period-positive content on social media. But when we market products that promise to make periods “invisible” or “undetectable,” aren’t we still reinforcing the idea that menstruation is something to hide?

These aren’t questions with easy answers, but they’re worth discussing. And that’s really what Flow is all about—starting conversations that should have been happening all along.

A Book That Changes the Conversation

Reading Flow was both enlightening and, at times, infuriating. Enlightening because it filled in so many gaps in my understanding of menstrual history and culture. Infuriating because it made clear just how much unnecessary suffering has been caused by ignorance, superstition, and misogyny disguised as medical or religious authority.

But ultimately, this is an empowering book. By understanding where period stigma comes from, we’re better equipped to challenge it. By learning what science actually knows (and doesn’t know) about menstruation, we can make more informed decisions about our health. And by recognizing that the shame we feel isn’t inherent but culturally constructed, we can begin to let it go.

Whether you’re someone who menstruates, someone who loves someone who menstruates, or simply someone interested in how culture shapes our understanding of bodies and health, Flow offers valuable insights. It’s a reminder that knowledge is power, and that sometimes the most radical act is simply telling the truth about our bodies.

I’d love to hear your thoughts if you’ve read this book or if these topics resonate with your own experiences. How has period stigma affected your life? What changes have you seen in attitudes about menstruation? Let’s keep this conversation going in the comments—because that’s exactly what Stein and Kim would want. After thousands of years of silence, it’s time we all started talking about periods openly and honestly.