The 28-day cycle, and other myths of menstruation | Jen Gunter: Full Interview

I'm an active physician and I see patients in the office. I see a lot of communication issues — I hear from patients online about difficulties interacting with their health care provider, or about people who have fallen down rabbit holes with disinformation and gone down routes that may not have been helpful to them.

I realized some time ago that medicine had a big communication gap, and I view everything I'm doing as trying to close that gap: giving people information about their body so they can be informed. You can't make an empowered, educated decision about your body without the right information on the subject.

I want people to have the information so that when they're in the office with a medical provider, they can advocate for good care and know what's harmful and what's normal.

I want people to have the information so when they encounter things online, they'll know what's factual and what's not. I'm very interested in educating the public about science and medicine because there are huge gaps in communication. You can't be an empowered patient without accurate information. I view myself as someone trying to close those gaps by getting knowledge about your body out to people, so they can advocate for themselves in the doctor's office and sort through what's factual online and what is likely snake oil.

Hi, my name is Dr. Jen Gunter. I'm a San Francisco Bay Area OB/GYN, author, and health communicator, and my latest book is Blood: The Science, Medicine, and Mythology of Menstruation.

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The science of menstruation

For many years — thousands, maybe longer — society has viewed menstruation as something toxic or dirty, potentially dangerous to men, something that reflects a problem with the body. The ancient Greeks believed that men were perfectly in balance fluid-wise and women were not, and menstruation was evidence of that. They believed every cell in the body was overly moist, so if you can't handle your fluid appropriately, you need an overflow valve — and that's really what they thought menstruation was. It was a physical sign of inferiority, and that banner has long been carried by medicine, by many societies, and by many religions. It's been weaponized against women as a sign of inferiority, when really it's simply a biological function.

We know very little about how women historically cared for their periods, because almost everything written historically was written by men. Some people have gone through diaries of women from the 1700s and 1800s to understand what they might have done, and there's information about how many pairs of underwear you might need or other things — but almost no information about how they cared for their menstruation. That's probably a sign of how much of a taboo the subject is, which is related to the shaming of women and women's bodies, and possibly also because they thought everybody knew how to take care of it, so it didn't need to be written down. Either way, we have a real information gap about how women handled periods historically.

There are so many potential negative outcomes when people don't know about the menstrual cycle. We've often framed these as the risk of unplanned pregnancy and not being able to time pregnancy, and that's certainly one issue. But when people don't know what's happening to their body — what's normal or abnormal — they don't know when to seek care or whether what's happening is totally expected. There's also the problem of not knowing the best care when you are suffering: if you don't understand the science, therapies might not make sense to you, or snake oil you find online might sound like a good idea — whereas if you understood the biology, you'd say, "Wait, no, that's not something I should be paying attention to." Knowledge about contraception is very important, but it's only one part of the menstrual cycle, and not everybody needs contraception. People live their whole lives with this cycle and need to understand the biology.

Historically, education about the menstrual cycle has been dismal. I can't speak for every country, but I speak with people from many different places, and they all have basic questions about the biology of the reproductive tract. In the United States, what people are taught seems to vary from nothing to very little, and it's framed entirely in the context of pregnancy and preventing pregnancy — not about what menstruation is and what it means for a person's body. It's a very narrow view that doesn't provide much useful information.

Everybody should care about menstruation, because if you're watching this, you're only here because somebody had a menstrual cycle. The menstrual cycle is the wheel that drives humanity. It was an essential part of human evolution — getting the big brains we have required a menstrual cycle. If you're using a computer, driving a car, or reading a book, all that technology comes to you because of the menstrual cycle. Somebody had a menstrual cycle to bring you into this world. You might know, love, or have children with someone who has a menstrual cycle, and knowing that information could help you care for family members, friends, or lovers when they're having problems. We should know more about our biology. And for centuries, possibly thousands of years or longer, medicine has been medicine for...

Medicine has been medicine for men, and we need to step back from that and be far more inclusive. A good way to start is to learn more about the menstrual cycle.

For thousands of years, people have used euphemisms to talk about periods, because if a topic is treated as shameful, you can't use the word. One term I've heard a lot, which I hate, is "the rag," which relates to people having to use rags as menstrual products. Two I actually love, because I like the idea of subversive euphemisms, are "there's communists in the fun house" and "a party at the Red Roof Inn." Shark Week is another one. I love the idea of a graphic euphemism: if you think it's shameful and don't want me to say I'm bleeding or I'm menstruating, I'll say something far more graphic instead — so, Shark Week.

The word menstruation comes from both Latin and Greek roots meaning monthlies or a monthly occurrence. It reflects the idea that the menstrual period was expected to come about once a month, like the moon. That doesn't mean your menstrual cycle is tied to the lunar cycle at all — it's simply related to a monthly occurrence. It has nothing to do with the word "men," which people always ask about, and everything to do with the word "month." Many people have historically believed the menstrual cycle runs every 28 days.

The idea that the menstrual cycle is 28 days appears in many textbooks, but there is no scientific proof for it. That figure is an idealized or most common cycle—possibly an average at certain ages—but there is wide variation depending on the classification system used: anywhere from 24 to 38 days, or from 21 to 35. There is no good scientific or even historical evidence that most people have a 28-day cycle. In fact, there is considerable variation even from cycle to cycle, which many people don't know: a 26-day cycle one time and a 32-day cycle the next can be perfectly normal. A swing of up to 7 days in either direction is normal, built-in variability.

Only a few mammals menstruate

Relatively few mammals menstruate: humans and some great apes, some bats, the spiny mouse, and the elephant shrew—a motley crew of species. Menstruation is thought to have evolved four separate times—once for humans and the great apes, and three other times for the other animals mentioned. Every other mammal has an estrus cycle, which is a little different: they don't shed the uterine lining, but we do.

A menstrual cycle means the lining of the uterus has undergone a change called decidualization. In humans this happens after ovulation and is driven by the release of progesterone. Decidualization is a real physical change in the tissue: think of the decidua as a catcher's mitt in the uterus, all prepared and ready for an embryo. Without it, implantation cannot occur.

The decidua is so thick because humans have an incredibly invasive placenta—one that wants to deliver a lot of oxygen to feed those big brains. An invasive placenta has to be contained, or it could grow through the uterus and cause problems, so humans evolved an especially thick decidua to deal with it. In addition, the decidua in some ways senses embryo fitness and helps regulate which pregnancies take and which end as very early miscarriages.

When you don't get pregnant in a cycle, you're left with this big, thick tissue that has nowhere to go and cannot be reabsorbed by the body. The only way to get rid of it is to shed it. Menstruation involves chemical changes that cleave the decidua from the uterus, opening blood vessels that push the fluid out along with the shed tissue, and then the cycle can start anew.

With an estrus cycle, decidualization is still needed for a pregnancy, but the trigger comes from the embryo itself. There's no catcher's mitt waiting in advance; once the embryo makes contact, the changes that trigger decidualization happen. If there's no embryo, there's no decidualization—nothing needs to come out, and any tissue present can easily be absorbed. That's the essential difference between a menstrual cycle and estrus.

The cycle begins with bleeding

One analogy I often use for menstruation is pulling the sheets off the bed: you didn't get pregnant, so you pull the sheets off and remake the bed for company again. To be clear, we are not all meant to get pregnant—this is simply a description of the physiology and why it exists this way.

If menstruation is pulling the sheets off, the menstrual cycle is already starting again while you're menstruating—like ironing the sheets and getting them ready as you pull them off. The cycle begins on the first day of bleeding. During that time, follicles in the ovary that have been on roughly a 300-day journey are ready to accept signaling from the brain to potentially ovulate. They are triggered first by follicle-stimulating hormone and later by luteinizing hormone. These hormones cause the follicles to develop, and fairly soon one becomes the dominant follicle.

The follicles produce estradiol, the most potent estrogen. There is constant communication between the estrogen produced by the follicles and the brain, and the estrogen also travels through the body, stimulating breast tissue, affecting the immune system, and causing the uterine lining to grow. When estradiol reaches a certain level, the brain–follicle communication triggers a surge in luteinizing hormone, which triggers ovulation: the follicle releases an egg. Afterward, the leftover follicle tissue organizes itself into a structure called the corpus luteum, which produces progesterone.

Progesterone then takes over, converting the estrogen-thickened cells of the uterine lining into decidua—tissue capable of accepting an embryo for implantation, which is required for pregnancy. The corpus luteum has a natural lifespan of roughly 10 to 14 days. If no pregnancy occurs to signal the corpus luteum to persist and help form a placenta, it stops producing progesterone. It is this withdrawal of progesterone that triggers menstruation.

Beyond preparing the rest of the body for pregnancy, progesterone's primary role is controlling decidualization to make the endometrium receptive. Without it, implantation cannot happen. In an estrus cycle, by contrast, signaling originates from the embryo itself. In humans, it is like a restaurant preparing a dish whether or not you show up; in an estrus cycle, the dish is prepared only after it has been ordered by the presence of an embryo.

Phases of the Menstrual Cycle

The menstrual cycle is typically divided into two phases:

• The Follicular Phase: Encompasses follicular development in the ovaries and the hormonal communication with the brain via follicle-stimulating hormone (FSH). While some consider menstruation a separate phase, it is technically part of the follicular phase.
• The Luteal Phase: Begins with the surge of luteinizing hormone (LH) and ovulation. It is characterized by the ruptured follicle transforming into the corpus luteum and secreting progesterone.

The Mechanics of Ovulation

Ovulation pain, known as mittelschmerz, is believed to be caused by the release of prostaglandins triggering cramp-like sensations rather than an explosive physical event. Rather than bursting dramatically from the ovary, the egg is released as enzymes dissolve surrounding tissue.

Ovulation does not strictly alternate between the left and right ovaries each month like a tennis match; the pattern is largely random, with one ovary potentially releasing eggs for several consecutive cycles. However, if one ovary is surgically removed, the remaining ovary compensates by handling all ovulatory cycles, though the exact signaling mechanisms behind this compensation remain poorly understood.

Birth Control and Menstrual Myths

A common question is whether suppressing periods with hormonal birth control causes harmful buildup in the uterus. Daily hormonal contraceptives expose the body to progestins continuously rather than just during the second half of a cycle. Broadly speaking, while estrogen stimulates lining growth, progesterone stabilizes and limits it. Continuous exposure keeps the uterine lining from thickening, resulting in lighter periods or none at all, leaving nothing that needs to be shed.

Another common myth is that menstruation serves to eliminate toxins from the body. Menstruation is not an excretory process; bodily waste and toxins are processed by the liver and kidneys, not the uterus. Suppressing menstruation through continuous contraception poses no risk of toxin accumulation.

Inclusivity in Menstrual Health

Discussions around menstruation require inclusive terminology. While most who menstruate are cisgender women, trans men and non-binary individuals also experience cycles. Conversely, many women do not menstruate, including postmenopausal women, trans women, and individuals who have undergone hysterectomies or oophorectomies. Using broad terms like "people" accounts for these variations accurately.

If menstruation hasn't started by age 16, it's time to discuss this with your medical provider. If it starts before age 8 or 9, that's also definitely a time to talk to a provider. The age of onset has nothing to do with when menstruation stops — they're different biological phenomena. Some people wonder whether starting early means stopping early, and the answer is no. The average age for menstruation to stop is around 51, with a typical range of 45 to 55 — a wider range than for onset.

Menopause between ages 40 and 44 is called premature menopause. If menstruation stops before age 40, it's typically called primary ovarian insufficiency, and that needs to be investigated for many different reasons.

The impact of menstrual pain

Menstrual pain is unfortunately a common experience, ranging from a minor symptom to something incredibly intrusive, painful, and damaging. It can result in missed school, missed work, multiple surgeries, and all kinds of medical therapies — along with the expenses of all of that. We know it's a significant problem, but because it's understudied, it's hard to know the exact significance. Also, many people just have to suck it up and go in because they don't have financial choices, so understanding the true potential impact is challenging.

Symptoms across the cycle

A constellation of negative symptoms can be associated with the menstrual cycle. Some occur around the time of menstruation, and some are potentially triggered around ovulation.

• Premenstrual syndrome (PMS) is a constellation of symptoms that happen only in the luteal phase, after ovulation. These can include breast tenderness, moodiness, feelings of hopelessness or anhedonia, and food cravings, which are very common.
• Menstrual cramps happen either the day before or starting with menstruation, and vary from mild to incredibly severe.
• Menstrual diarrhea happens at the same time, right before or during menstruation.
• Mittelschmerz is pain with ovulation, which we believe is actually more related to muscle spasm triggered by the chemicals released at ovulation.

PMS is the broader term for this constellation of symptoms. Premenstrual dysphoric disorder (PMDD) is much less common. Some think of it as a variant of PMS — probably a more severe form — though truthfully we don't know whether they're different or part of the same spectrum. PMDD has more severe symptoms, a significant impact on activities of daily living, and tends to involve more depressive symptomatology.

Why cramps happen

Menstrual cramps are called dysmenorrhea. Primary dysmenorrhea is painful cramps not related to another medical condition; secondary dysmenorrhea means cramps thought to be related to something else, the most common example being endometriosis.

Cramps are a very common experience — 70 to 80% of people will have them — and they vary in intensity from person to person. We think they exist as part of the mechanism to stop bleeding. The chemicals released with ovulation cause the tissue, the decidua, to cleave off the uterus. Among those chemicals are prostaglandins, which trigger pain and cause the uterus to contract.

When the decidua peels off — like peeling off a scab — you're left with open blood vessels that had thickened and developed to provide nutrients to an embryo, so there's a lot of bleeding. The chemical soup then works to stop it: substances cause vasospasm, contracting the blood vessels, and the uterus cramps down, much like putting pressure on a wound. The cramping itself is painful, the reduced blood flow is painful, and some of the chemicals involved can also affect pain thresholds. So you have muscle cramps, prostaglandins floating everywhere, and reduced blood flow — that's what produces cramps. There's a wide range in how people experience them and how they respond to therapy.

About 12% of people who menstruate also get menstrual diarrhea, which comes from the prostaglandins released into the circulation — prostaglandins cause diarrhea in the bowels. We need prostaglandins, though, because they're part of triggering menstruation, triggering the release of the decidua, and stopping the bleeding.

Without prostaglandins, menstruation would have to happen a different way, or we'd need a different type of menstrual cycle, so they are a critical hormone. Prostaglandins matter throughout the body in many ways—it's not just a menstrual-cycle-related chemical—but as far as menstrual pain and menstrual diarrhea, they are the big troublemakers.

Many people ask whether this seems like a poor evolutionary design: if many people have pain and 12% have diarrhea, and some people have very heavy periods that can lead to anemia, this seems troublesome. There are a couple of answers. Obviously, we don't know what menstrual cycles were like 10,000 years ago. But there is a romanticization of nature—the idea that everything in nature works perfectly—and I think nature's motto is best summed up as "just good enough." Evolution doesn't care about an individual person's suffering; it only cares whether a design works well enough to perpetuate the species. That's another reason everyone should understand menstruation: the pain and problems involved in perpetuating the species have been uniquely borne by half the population.

How do you explain menstrual pain to someone who has never had it? For perspective, the pressure generated by menstrual cramps can be the same as the pressure generated during labor when pushing. Some people have equated labor pain to cutting off a finger without anesthetic. There are even menstrual cramp machines meant to help people appreciate how much it hurts, though I'm not sure how accurate they are, since menstrual pain is a deep visceral pain while those devices create surface pain. The important point is that it can be very painful for many people, and that pain is often minimized when it shouldn't be. If cramps are affecting your activities of daily living, that's the time to talk with a medical provider—what that means will differ for different people, but if they're affecting you, a loved one, your child, or a friend that way, it's time to seek care.

Beyond the suffering itself, some data suggests untreated pain can have other effects on the nervous system: it may raise your rate of having other pain conditions, because pain primes the nervous system in many ways. This is an active area of research, and we don't understand the full implications. But people shouldn't be suffering in the here and now—we don't need fancy science about downstream effects to say that pain needs treating. If you have pain, it should be treated and recognized. And a decision also needs to be made about whether the pain needs investigating as a possible warning sign that something else is going on.

One of the most common treatments for menstrual pain is non-steroidal anti-inflammatory drugs, or NSAIDs. These drugs block prostaglandins, which is why they're very effective. However, they don't work for some people. When they don't help, that could be a sign that something else is causing the pain, like endometriosis—though for some people they simply don't work well, and we don't really understand why. Still, taking medications that block prostaglandins is an evidence-based approach to treating menstrual pain.

I'm often asked whether people should track their menstrual cycles, and I always ask: what's the reason you think you need to do that? If you're having symptoms and you're not sure whether they're related to your cycle, then what we call a menstrual calendar or menstrual diary can be very helpful. For example, I can't diagnose PMS unless I know your symptoms always start after we think you've ovulated. Tracking can also help sort out whether pelvic pain is really tied to your period or is unrelated to your cycle, or whether headaches are menstrual migraines. Two or three months of data can be genuinely useful to share with your medical provider.

But we're also seeing an explosion of the "quantified self" — tracking for the sake of tracking, in the belief that you'll glean bits of information to optimize your body. We have no data to support that.

Accuracy problems with tracking apps

One issue with menstrual tracking apps is that many use proprietary data or proprietary algorithms that researchers can't analyze to see how accurate they are. If an app is just using calendar input to predict your next cycle, that can be quite inaccurate. In one study of women who tracked their cycles, when their period didn't arrive when the app predicted, the women blamed their bodies rather than blaming the app for an incorrect prediction — meaning the app made them less informed about their bodies, not more.

Cycle-based training claims

There's a lot of talk on social media about athletes using their menstrual cycle to optimize performance — that you should only lift weights at a certain time of your cycle and do cardio at another. None of that is grounded in good science. There is no robust data saying that during the first week of your cycle you need one kind of exercise and on days 10 to 15 another. Evolutionarily, that also doesn't make much sense to me — our ancestors couldn't have chosen what they could or couldn't do when they needed to gather food and water. It's probably not fair to bring that into it, but it always comes to mind.

It is true that if you're trying to optimize your fitness, there may be times of the month when you'd rather avoid certain activities — if your breasts hurt, maybe skip upper body work; if you have menstrual diarrhea, a long run may not work. Those are intuitive; you don't need an app to tell you that. If you're a professional athlete, where missing two days of arm training at a critical time could mean the difference between gold and silver by a millimeter or a millisecond, then a workout schedule that accounts for when you can or can't do certain exercises may genuinely help optimize your training. But for everybody else, we just don't have data beyond "listen to your body" — if something hurts at a certain time, do that exercise when it doesn't. We certainly have no good data showing that hormonally you'll build muscle better in specific ways at different times of the cycle. That data just isn't there.

The dark side: legal risks of menstrual data

So it comes down to trusting your body — with the caveat that we can't be sure apps will help you do that. There is a dark side to menstrual tracking apps that people absolutely need to know about, whether they're tracking just to see what's going on or using an app as part of a fertility awareness method. That data can be subpoenaed by a district attorney and used to build a case against someone if they live somewhere abortion is illegal and people are prosecuted for having abortions — or even for the suspicion that they might have had one. When you're collecting this data, you don't know that you might want to seek an abortion in one, two, or three months, but the data showing when your last period was is being collected, and cases have been built from data harvested from people's phones.

If you live in an area where you don't have the legal right to an abortion, or where prosecution for abortions is happening, it's very important to be mindful about how you use these apps. Many people are unaware of how much data their phones collect — we've all had the experience of mentioning a meal or an activity and seeing an ad for it on social media within seconds. It's not a stretch that data pinning you to your menstrual cycle could be harvested by someone. We've already seen pharmacists in some states refusing to dispense medication because it could potentially cause a miscarriage — even for someone taking it for an immune system problem — and requiring proof that they couldn't possibly be pregnant. So I don't think it's a stretch that in some places this kind of data could lead to all kinds of problems down the road.

People need to be very mindful about where we're going. Ignorance about the menstrual cycle is clearly very common, even among medical providers, and weaponizing that ignorance is essentially becoming law in many places. These are troubling times, more than ever, and this is when people need to actually know the facts so they can speak up and hopefully turn the tide. In many parts of the United States we are seeing a shift toward viewing women solely as breeders, as if your life outside of pregnancy has less value than your role in carrying a pregnancy. Pregnant people are unable to get the medical care they need because of potential harm to a fetus—we have seen people denied chemotherapy and denied cancer treatment because they are pregnant and live in places where they can't get an abortion. This amounts to reducing half the population to potential breeders, and I don't think we can sound enough alarms about that.

Everybody needs to know about menstruation. If we can't talk about it or share knowledge about it, the implication is that it's shameful and doesn't matter. We know the menstrual cycle has a significant impact on the half of the population that has one, and much of that impact is understudied. We don't have enough knowledge about how it can affect medications—and I'm not talking only about medications for the reproductive tract, but how it affects taking your blood pressure medication, your cancer care, all of these things. We are really behind in that area. If you have a menstrual cycle, or love someone who does—and everyone came from someone who had one—you should want everybody to access the same level of care.

People with menstrual cycles can also have related problems: heavy periods, painful periods, and medical problems connected to their periods. We want everybody to know about that so people aren't suffering at home—knowing how much blood is too much, how much pain is a concern, whether your period has started too late. These things matter so you can advocate for yourself. If we're not talking about menstruation, how do people learn about them? They don't. They may think their body is uniquely broken, or they may not realize anything is wrong and fail to seek care when they have a medical problem.

The only ones served by not talking about menstruation are the patriarchy and the political powers that exist. It's not shameful. We deserve to have conversations about it, to know what's happening to our bodies, and to have a say in medicine and research so everybody can access quality care.

Everybody who has a menstrual cycle will at some point have that cycle stop. The winding down of the menstrual cycle is the menopause transition, and the stopping itself is menopause. Yet even though everyone will experience this, very few people understand what it is or are aware of the biological changes ahead. To me, that's unacceptable: this is a universal experience, and it's barely spoken about at all.

Depending on how long you live, you may spend a third or even half of your life in menopause. Understanding it matters not just personally but medically. We don't know whether medications act differently once somebody has finished menstruating—and not just reproductive medications, but cancer care, hypertension care, diabetes care, all of it. If you're going to live a third or half of your life in a particular phase, we should know about that phase.

Menopause is not a disease

Menopause is often framed as a disease, and it isn't. We don't consider puberty a disease, or pregnancy a disease, and menopause is not a disease either. That thinking is based on pharmaceutical marketing from the 1960s, which suggested that women were only now experiencing menopause because life expectancy had risen past age 50. But that erases everybody's grandmother and great-grandmother, and we know it's simply not true—nobody ever asks that question about life expectancy and men, do they?

Most animals die after they finish reproducing: they keep reproducing right up to the end. Animals that keep living after reproduction ends are quite uncommon—humans are the big one, orcas are another, and there may be a few other species, though they aren't as well studied. So the question is: if everything about reproduction is evolution getting the next generation into the world, how could menopause—where reproduction is no longer possible—be beneficial?

The grandmother hypothesis

We think it's beneficial because of what's called the grandmother, or wise woman, hypothesis. When you finish menstruating, you finish having more offspring. And when you're no longer running around after a seven-, eight-, or ten-year-old, you're able to help your children by offloading some of their work. Historically, having a grandmother in the family unit meant an extra pair of knowledgeable hands that weren't occupied with child rearing: someone who could help gather food, help with child care, help build shelter and find water, and pass on historical knowledge—what to do during a drought, what to do when the cold weather came. All of that wisdom was passed down along with the helping hands.

The idea is that menopause represents evolution playing the long game: you're not helping your immediate offspring, you're helping your grand-offspring live longer or produce more offspring. It's not your genetics per se being passed along, but your grand-genetics that you're supporting. That's the main theory for the existence of menopause—that it was very beneficial evolutionarily.

We retain our power as we age. Menopause is said to have occurred when you are one year past your last period. If you're between the ages of 45 and 55, that is the expected range for it to happen.

Just as hormonal changes lead up to the first period, hormonal changes lead up to the last one. That time of hormonal change is known as the menopause transition, though you may also have heard it called perimenopause or pre-menopause. The transition lasts anywhere from four to seven years, maybe a bit longer, and it is a winding down of reproductive hormones — but not a smooth decline. In fact, it's much more chaotic: some months you may produce more estradiol, the main estrogen, than you normally would, and other months less. Over time, menstruation starts to space out, with longer and longer gaps, and eventually periods get skipped. When people are skipping periods, they are generally believed to be about one to three years from their final period.

Medically, the word menopause describes the day of the final period — but you never know it's that day until afterwards, and it doesn't really signify anything. Everything after that final period is medically called post-menopause, although colloquially most of us use "menopause" to describe the final period and everything afterwards, for simplicity's sake.

Timing and categories

The typical age for the final period is between 45 and 55. If it happens between ages 40 and before 45, that's called premature menopause. If periods stop before age 40, it's called primary ovarian insufficiency. People can also have surgical menopause — having the ovaries removed puts you into menopause. This is categorized by age: surgical menopause at 45 or older falls in the typical range, while under 45 it's considered premature.

Hormone testing

A lot of people ask about hormone testing for menopause, and my answer is: you got through puberty without hormone testing and everything worked okay. If menopause is happening when we expect it to happen, we don't need hormone tests. If you're 49, we expect your periods to stop — that's not a surprise. If you're 39, we don't expect them to stop, and you do need hormone testing. What matters is whether the change is happening at a predictable time.

It's also important to remember that other medical conditions can cause periods to stop, so sometimes testing for other things is needed. But reproductive hormone testing is not a reliable way to see where you are in the menopause transition. It only reliably tells you that you are menopausal once you are well past your final period — which doesn't help, because by then you already know. Nothing based on hormone tests can predict what's coming. We don't treat someone over 45 based on hormone tests; we do recommend testing under 45, because that's not when menopause is expected. If you're 42 and your periods stop, we need to know whether it's premature menopause or another medical condition. It all comes down to whether the changes are happening when they're expected.

Symptoms

Menopause is associated with a large constellation of symptoms, and because it has historically been understudied, we don't have a full handle on how many symptoms are common or what percentage of people experience all of them. The ones we know a lot about, that are quite common and often part of the general conversation, are hot flashes and night sweats, known as vasomotor symptoms. Other common ones include vaginal dryness, irritation, or pain with sex; brain fog; palpitations; and joint pain. Those are probably the more common ones we hear about, but the list is quite long.

The menopause transition — the hormonal chaos leading up to menopause — has an average duration of about four to seven years, but symptoms don't always correlate with that. Some people have their worst symptoms early in the transition, some towards the end, and some around the time of the final period or even afterwards. A good way to think about this wide variation is by analogy to pregnancy: there's a wide constellation of symptoms — some people have severe morning sickness and others none at all, some have a lot of swelling and others don't. We're used to that range of experiences with pregnancy, and it's a similar way to think about the range of experiences with menopause, which crosses many domains.

Menopause brings many symptoms, and medicine does have a toolkit to manage many of them. But one of the most important things is a good health foundation going in — and that is exercise. I don't like that answer any more than anybody else, but we can't deny its impact on all the domains menopause touches. Menopause changes your trajectory of risk for type 2 diabetes, heart disease, dementia, depression, and osteoporosis. Exercise touches all of those domains: you get stronger bones, more muscle mass, lower risk of type 2 diabetes, benefits for your heart, help with mood, and protection against dementia. Medications can only do so much — if exercise were a drug, it would be the thing we'd give to everybody. And it's not just aerobic exercise; strength building and resistance training are super important. That is the most important foundation for treating menopause.

Menopausal hormone therapy

One treatment people have heard a lot about is menopausal hormone therapy, or MHT. We used to call it hormone replacement therapy, but we no longer use that term, because we are not replacing estrogen you "should have." We expect menopause to happen and estrogen levels to change — we just don't expect people to suffer. So it's a therapy.

MHT is the gold standard treatment for hot flashes and night sweats — vasomotor symptoms. There are other options: a new drug designed specifically for hot flashes, and some drugs from the epilepsy and depression categories that are also used for them. But MHT remains the gold standard. For vaginal changes, we use vaginal estrogen and other local products; we don't generally recommend taking MHT solely to treat the vagina, because local products work better there.

Should I take it?

The big question people ask is, "Should I take it?" Like any medication, the question is: do you need it? MHT can help many parts of menopause, but not all, so you only want to take it for what it can do. There is no broad agreement that everyone should be on it during menopause — we do not recommend it universally as preventative care.

I think of the reasons for starting MHT as traffic lights. The green light indications are evidence-based: hot flashes and night sweats, and prevention of osteoporosis in people at high risk. These are listed on the US packaging label, the FDA allows advertising for them, and good studies support them.

Yellow light reasons might help some people and not others, requiring a much more individual discussion. Examples:

• Depression in the menopause transition. Some studies show estrogen can help — but interestingly, not after menopause. Someone two years past her final period wanting estrogen for depression wouldn't be an evidence-based recommendation; someone with irregular cycles in the transition might be a candidate.
• Joint pain. The studies aren't great, but it might help some people, so it may be worth a trial.
• Type 2 diabetes risk. Some data suggests MHT may reduce its incidence, so for someone at very high risk it might be part of a discussion with your provider — but there's no global recommendation for prevention.

The red light reasons — not recommended — are prevention of dementia or Alzheimer's disease, and prevention of cardiovascular disease. There may be some benefits to starting early for cardiovascular health, but that hasn't reached the threshold of a universal recommendation.

We also do not recommend MHT for brain fog: quite a few studies show it has no short-term impact on brain functioning. One caveat: if you're sleeping very poorly because of hot flashes — up eight times a night kicking the sheets off — a trial of MHT to see whether better sleep improves your brain function may well be worth it. But for brain fog alone, no, it doesn't work for that.

Menopausal hormone therapy also doesn't work for weight gain in menopause, which is another thing people frequently ask about. Whether or not you should start it really depends on whether you have a symptom it can help or possibly help, based on your individual risk profile. If it's a safe therapy for you, it may well be worth trying. And like any therapy, if you start it and aren't seeing the benefit you want, it should be reassessed.

One symptom that isn't discussed enough in the menopause transition is menstrual irregularity. Skipped periods are part of the transition, but people can also have heavier periods, and they can accumulate medical conditions that contribute to heavy bleeding—specifically fibroids and a condition called adenomyosis. For many people, hormones are an important part of controlling bleeding problems.

One common approach is the estrogen-containing birth control pill, because it controls heavy bleeding well, provides the benefit of estrogen, and offers contraception for those who need it. If someone is at low risk for problems related to the estrogen-containing pill, they can take it up to age 55. Other options include a hormonal IUD to treat heavy periods, and if people want to start menopausal hormone therapy, they certainly can, at standard doses.

Why pharmaceutical preparations matter

Menopausal hormone therapy means pharmaceutical preparations from a pharmaceutical company—a pill, a patch, a transdermal lotion, or a gel that comes labeled from the manufacturer. It is very important that products be pharmaceutical, because making hormones reliably absorbable, whether from the gut or across the skin, is quite challenging and takes years of research. When I prescribe a pharmaceutical patch or pill, I know exactly how much is being absorbed, what dose protects the bones, and what dose helps with hot flashes.

With a compounded product, you have none of that research and development. You don't know if it will be absorbed well or whether the vehicle it's compounded with has ever been studied. Pharmaceutical products are batch tested, so we know they contain what they claim—compounded products are not. There can be issues with absorption and dose. Compounded products also don't carry the same warning labels as pharmaceutical products, which creates an illusion of safety: people see a warning label and get concerned, and if they don't see one, they assume there's no need for concern. But it's simply that US rules don't require the label.

I would include injected hormone pellets as part of compounded hormones. Pellets often deliver very high doses of estrogen or testosterone or both, depending on the pellet. They're not batch tested and are associated with many adverse events. A big problem with compounded products generally is that adverse events often go unreported. Using a pharmaceutical preparation is what gets you a safe dose and something that has been studied and is known to work.

The "bioidentical" question

A common objection is, "But I want to take bioidenticals." Bioidentical is a marketing term with essentially no medical meaning. The belief is that it means a hormone identical to what your ovaries make—but being the same as what your ovaries make doesn't make a hormone safe. I could extract estrogen from ovaries and give it to someone, and over time give them endometrial cancer, and that would be estrogen from an ovary. What makes something safe is that it has been tested and studied.

Here's the kicker: almost every pharmaceutical hormone I would prescribe could be considered bioidentical, because it's all estradiol, generally made from soybeans, and it all comes from generally the same plant—plant as in factory, not something that's grown. Whether you're a compounding pharmacy mixing up raw estradiol or a pharmaceutical company purchasing it, it's coming from the same place. There's no special soy estradiol tree they pick their hormone from.

The only exception is conjugated equine estrogens, which are extracted from horse urine—technically the only "natural" estrogen, since they're unchanged from how they're found in nature. But if I'm prescribing estradiol for you, it is plant-based and bioidentical, and you can get it from a pharmaceutical company.

Testosterone

Testosterone is not part of menopausal hormone therapy—there is no universal recommendation to add it in. We don't recommend adding it for fatigue, brain fog, or hot flashes. Think of testosterone as a medication for a specific indication, and the only indication is for people suffering from libido or desire problems who have a relationship that isn't the cause of those issues, and who have explored other therapies. For example, mindfulness-based therapy is highly effective for libido and desire disorders, and there's a lot of disinformation out there about what desire actually is, so I always encourage people to get educated on the subject. But that is the only evidence-based indication.

Testosterone's only evidence-based indication is for desire-related issues. So how do you sort the snake oil from science online, given how much medical content is out there about the menstrual cycle or menopause? I have a few good rules of thumb.

Rules of thumb for evaluating medical content

First, if something sounds too good to be true, it probably is. There is no influencer or doctor who has discovered a secret no one else knows about—if the information is real, we all know about it. Be very careful about people making bold promises. You should be able to look the claim up, and if it's true, you should find major news stories about it.

Second, does the person sell supplements? Supplements are untested, unregulated pharmaceuticals. If I sold "Dr. Jen Gunter's birth control pill," you would rightly suspect my information about contraception. So when someone makes money advertising supplements or has their own brand, consider all of their medical information contaminated—how do you know it isn't a subtle sell for their products?

Third, be mindful about what you read online, because you need to fact-check immediately. If you keep engaging, it might stick in your brain.

How to fact-check

Take the subject matter, put it into a Google search, and add the relevant professional society—for reproductive health, for example, ACOG (American College of Obstetrics and Gynecology), SOGC (Society of Obstetricians and Gynecologists of Canada), or the Menopause Society. Put your question first, then the society's name. That forces the algorithm to bring content from those societies to the top.

The big problem with doing your own research online is that many people end up with incorrect information, because snake oil sellers are really good at search engine optimization. Adding a medical professional society trumps that. You could also use the CDC or the WHO, or ask your doctor which medical society they trust for gut or brain health questions and search with that.

Getting the care you need

When seeking medical care, I encourage people to write down the things bothering them—which symptoms they wish would go away. It can be a list of two things or twelve. That helps your doctor work through the list with you; it might take more than one visit if there are many issues, but it lets you approach things systematically.

If you're not getting the care you need, speak up, as long as you feel safe doing that. If you don't think your symptoms have been heard, it's very valid to say, for example: "I read at the CDC that it's very safe for women to get vaccinated for COVID-19 in pregnancy. Why are you not offering me that? I'm pregnant." Coming in with information from medical professional societies shouldn't be necessary, but it can help if you're worried about not being heard.

Be mindful about who you're seeing. Is this person truly an expert—a physician board-certified in that area—or someone with less expertise, like a naturopath or a chiropractor? You may also want to check how the person is connected with industry. With doctors, you can look them up online and see if they've made money from pharmaceutical companies. But you can't look up whether a doctor has made money from a supplement company, and you can't look up naturopaths, chiropractors, physical therapists, nurses, or anyone else offering information online—so just be wary.

I would be very mindful about getting health advice from celebrities. They are not just like us, and the way they talk about medical conditions or physiologic states like menopause isn't always evidence-based. While it's great that people want to raise awareness, be careful about specific medical recommendations that come from celebrities.

I get asked a lot about supplements, and it's a big and sometimes confusing topic. Social media constantly delivers ads—both clear promotions pushing a vitamin and soft ads where an influencer mentions a product off the cuff, so you can't tell whether it was paid for.

The truth is that very few supplements have good evidence-based medicine to support them. The term "supplement" really means dietary supplement—something that fills a dietary shortfall. The best example is prenatal vitamins: there is good evidence for them because the average person doesn't get enough folate and other micronutrients from their diet to support a healthy pregnancy. We also recommend multivitamins for people who've had bariatric surgery, since the surgery prevents them from absorbing all the nutrients they need. These are examples of nutritional shortfalls—either because your physical state has changed, as in pregnancy, or because your gut isn't absorbing enough.

There are a few other indications along those lines. If someone has an illness and has trouble eating for four to six weeks, a multivitamin might be recommended to make up the shortfall. We also recommend supplements to treat specific deficiencies: with iron deficiency anemia, it's very hard to get enough iron from diet alone, so we might recommend an iron supplement. Some medications affect micronutrient levels too—for example, certain diuretics ("water pills") cause potassium loss, so some people need a potassium supplement. That's not an exhaustive list, but it's how to think about evidence-based use.

Then there's a second class: supplements with a reported medical benefit. In the United States, supplement companies can't actually claim their product does anything—they all carry FDA disclaimers. Within this class, some things are grounded in good science, like magnesium for constipation, while others are not, like black cohosh for hot flashes. Biotin for hair growth is another common one with no supporting data. There's a wide range—from well-supported to unsupported to somewhere in between—so each one has to be investigated and its evidence examined independently.

A third category lumps a whole bunch of vitamins, minerals, herbals, and botanicals into one product for "ovary support," "adrenal support," "thyroid support," "metabolism booster," or "fat burner." These insinuate a benefit for your organ, your health, or weight loss, but none of them are studied in any meaningful way—and many are actually adulterated.

That's a major concern with supplements: you don't know what you're getting. Products for libido, metabolism, or sports enhancement carry a much higher risk of contamination, and other products can be contaminated with lead or toxic molds and fungi. This is a huge problem—and it's exactly why pharmaceuticals have standards that prevent these things from happening.

Pharmaceuticals are tested for purity and contamination; supplements are not. So how do you decide whether to take one?

First, ask your doctor whether the supplement is actually recommended — for example, prenatal vitamins or supplements after bariatric surgery are legitimate, whereas "ovary support" products likely have no indication. Be mindful about whether you should take the product at all. If you do need it — say your doctor tells you that you have iron deficiency and can't get enough iron from your diet — then the best safeguard available in the United States is third-party verification. A USP-verified label means the product has been independently checked. That's really the best we can do, because in the US the government cannot require testing for purity. This matters both to ensure the product isn't contaminated with heavy metals, mold, or fungi, and to ensure it contains what it claims.

There are four ways to think about supplements:

1. Do you really need it? Is there good evidence to support it? Good sources include the CDC, the American College of Obstetricians and Gynecologists for reproductive health issues, and the US government's Office of Dietary Supplements — places to check whether it's recommended for the reason you want.
2. Who is recommending it? Someone selling a product, or someone relaying the recommendations of multiple medical societies? Look at the source of the recommendation.
3. Choose a product tested by a third party. It's the best we can do in the United States, but it's better than no testing at all.
4. Avoid certain categories entirely. Don't take anything marketed for sport enhancement or metabolism boosting, and be very wary of Ayurvedic products, which are very likely to be contaminated with lead — about 20% of them are. Metabolism boosters are more likely to be adulterated, and Ayurvedic medications carry a high risk of lead contamination.

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