It’s time to talk about period pain. Every month, every woman you know who’s pre-menopause and post-puberty bleeds from their vagina. Periods are one of the most basic facts of life. Any squeamishness around the subject is both ridiculous and harmful, because too many women are suffering in silence, grimacing through the agony they experience with their periods.

That’s right—agony. Not aches or discomfort or grumpiness, but very serious pain. Dysmenorrhea, the clinical term for painful menstruation, interferes with the daily life of around one in five women, according to the American Academy of Family Physicians. And yet there’s remarkably little research into the condition, say experts, and too many doctors are dismissive when presented with the symptoms.

Frank Tu, director of gynecological pain at NorthShore University HealthSystem, tells Quartz some physicians are taught that ibuprofen “should be good enough.” Clearly, this is not an adequate response to such severe pain. How severe? John Guillebaud, professor of reproductive health at University College London, tells Quartz that patients have described the cramping pain as “almost as bad as having a heart attack.”

Over the past two years, my period pain has become as severe as a slipped disc. I speak from experience, having had two slipped discs in my life, and doctors were so convinced I had a third that I was referred for an MRI. Every month I spent hours lying on the floor, unable to move, and literally crying out in agony. My hip and back muscles went into spasm, so that my body was twisted in an S-shape contortion whenever I stood—a condition that didn’t disappear when my bleeding ceased, but had to be treated with visits to a physiotherapist every four weeks.

Before I had my MRI scans, I told my primary care doctor that the pain seemed to be triggered by my period. He didn’t think this was relevant and ignored the comment. Later, when scans showed my discs were in place, the specialist said my pain was likely due to nerve inflammation—just one of those painful things that someone with my history would likely suffer from time to time. Once again, his eyes flicked to the side and he waved his hands dismissively when I asked if it could be connected to my menstrual cycle.

Next stop was the gynecologist, who gave me an ultrasound, told me everything looked normal, and, after a follow-up appointment when I said I was still in pain, suggested I take birth control without any breaks (the idea being that I would stop having periods altogether). When I asked about the risks, she told me it could lead to blood clots and increased risk of breast cancer—but that one in eight women get breast cancer anyway, so I shouldn’t be overly worried.

It turns out that taking the pill continually doesn’t completely stop periods, or the accompanying pain. And in the course of researching this article and talking to doctors, I realized I have all the symptoms of endometriosis—a condition that can’t be diagnosed with ultrasound, but only with surgical laparoscopy (more on this later).

For now, without official diagnosis, my monthly pain is something of a mystery. But once I started talking about period pain, I learned I’m not the only who puts up with this discomfort and confusion. Around half a dozen friends told me that they’d had similarly frustrating experiences—that they’d been shoved on birth control indefinitely, been prescribed Prozac to deal with their monthly bouts of depression, suffered through migraines and even vomiting whenever they had their period. The symptoms were diverse, but these stories all had one key thing in common: No one seemed able to get clear answers from their doctors.

The medical conditions linked to period pain

There are two main causes of period pain: Primary dysmenorrhea and endometriosis. The former is simply painful periods, with no certain medical explanation, that tends to affect women as soon as they start menstruation. But the distinction between the two conditions is not clear-cut, as many women suffering dysmenorrhea may have undiagnosed endometriosis. It’s estimated that while 20% of women have the former, around 10% of ovulating women in the US have endometriosis, and it takes on average 10 years to get an accurate diagnosis.

Endometriosis occurs when the tissue similar to that lining the uterus grows on other areas, usually within the pelvis, such as fallopian tubes and ovaries. This tissue has also been found on the bladder and intestines, and in rare cases, even in the lungs and brain. The body reacts to these lesions with inflammation and an attempt to cover it with scar tissue, and one of the most common symptoms is severe menstrual cramps. Left untreated, it can cause infertility. And yet there’s significant confusion about endometriosis—the causes, why some women are predisposed to the condition, if there’s a genetic component.

Meanwhile, the medical reasons for primary dysmenorrhea are largely unknown. Guillebaud says the pain is partly caused by uterus cramps, while Tu says a combination of sensory processing, local uterine inflammation, and uterine blood flow issues also come into play. The specifics of why some people suffer more than others is not well understood. “That’s a million dollar question that we don’t really understand,” Richard Legro, M.D., of Penn State College of Medicine, tells Quartz.

Existing treatments and the lack of research

Despite the sheer number of women who suffer from severe cramps, the existing treatments are limited. For both endometriosis and dysmenorrhea, patients can dull the symptoms by taking painkillers like ibuprofen, using the pill as contraception, which tends to reduce the flow of the period, or inserting an intrauterine system such as a Mirena.

If endometriosis is causing infertility problems, patients can have surgery to move the extra tissue—though it may well come back again. Symptoms vary hugely from patient to patient, and if less invasive treatments offer no relief, a hysterectomy is another option. “That’s far too over-the-top for lots of women,” says Guillebaud. “But it’s there at the end as a last resort and some people actually have to have that done.” But even a hysterectomy isn’t a complete cure, and the pain can persist.

As endometriosis can impair fertility, there is more research on this than on primary dysmenorrhea (though there’s hardly an abundance of research on either). For both conditions, doctors are unclear about the triggers, best possible treatments, and why it affects some women but not others.

Legro’s experience is instructive. Thanks to a previous grant, he and his fellow researchers found that sildenafil (also known as Viagra) can be used to treat dysmenorrhea. “We published our results in a high-impact OB-GYN journal and we feel we made a major contribution to treatment that everyday practitioners could use,” he says.

However, before it can be approved as a treatment, much more research is needed. For instance, Legro wants to look at the specifics of using sildenafil as treatment—the right dose, whether it should be taken vaginally or orally, what happens if it’s used over multiple menstrual cycles. Yet no one will fund the research. “I’ve applied three or four times but it always gets rejected,” he says. “I think the bottom line is that nobody thinks menstrual cramps is an important public health issue.”

A culture of silence

Clearly, the treatment options are far from ideal. But since periods are a condition that only affects women, it’s simply not given the attention it warrants. “Men don’t get it and it hasn’t been given the centrality it should have. I do believe it’s something that should be taken care of, like anything else in medicine,” says Guillebaud. Plus, symptoms can fade after childbirth (though, once again, no one knows why exactly). As “mother nature” can solve the problem, perhaps researchers who “want to make their name” don’t consider it an important enough area to do research, he says.

This indifference can trickle down to practicing doctors, who aren’t always prepared to take period pain concerns seriously. Guillebaud adds:

“I think it happens with both genders of doctor. On the one hand, men don’t suffer the pain and underestimate how much it is or can be in some women. But I think some women doctors can be a bit unsympathetic because either they don’t get it themselves or if they do get it they think, ‘Well I can live with it, so can my patient.’”

It may not be life threatening, but period pain is a painful condition that interferes with daily lives. So why is it widely neglected by the medical establishment?

“We need to talk about it on Oprah and national TV.”

Legro says that without a lobby championing the need for research, researchers won’t start paying more attention to the condition. He points out that public discussion of period pain is widely kept hush. For example, he says that in the US, several news channels are reluctant to use the words “vagina” or “menstrual bleeding,” which makes it practically impossible to discuss painful periods.

“We live in a country that doesn’t really want to face those disorders because they make us think of sex and abortion and embryos and all those ‘bad’ things,” says Legro. Judging by the treatment options and medical knowledge worldwide, other countries don’t have a much more reasonable reaction.

The solution, he adds, is for women who suffer from menstrual pain to come out of the closet. Period pain affects millions of women, and it needs to be talked about. “We need to talk about it on Oprah and national TV,” he says. “This is nothing to be ashamed of, it’s a common disorder, and it shouldn’t be ignored.”

So if your period causes pain, don’t grimace and bear it: Tell your doctor, your friends, your colleagues. We need to talk about period pain long and loudly enough for doctors to finally do something about it.

Correction (Feb. 18): An earlier version of this article quoted John Guillebaud as saying period pain can be “as bad as a heart attack,” when in fact he said it can be “almost as bad.”