There’s a mountain of reasons why you might feel fatigued or tired on any given day, many of which are easy to brush off. You probably just didn’t sleep well or properly fuel yourself, or you’re on your period or coming down with a virus. Or maybe you’re feeling supremely overwhelmed and stressed out—let’s not forget the mental load of existing in the US in the year 2025. But what you may not realize? Feeling like you’re trudging oh so lethargically through the day is also an especially common sign of sleep apnea in women.

It’s not exactly the stereotypical picture of the sleep disorder, which involves repeated pauses in breathing throughout the night. “When people think of sleep apnea, they often think of older, overweight men who have loud snoring and choking or gasping [while they sleep],” Shelby Harris, PsyD, a sleep psychologist and the author of The Women’s Guide to Overcoming Insomnia, tells SELF. A big part of why has to do with the research: It was first discovered in men with these symptoms and initially thought to be a “male disease”—bear in mind that research tends to conflate sex and gender identity—so no studies on sleep apnea included women until 1993. And once they did, researchers had no reason to suspect the condition would manifest any differently in women versus men.

But this turned out to be a misconception that hasn’t allowed us “to capture the disease accurately,” Christine Won, MD, medical director of the Yale Centers for Sleep Medicine and director of the Yale Women’s Sleep Health program, tells SELF. We now know that sleep apnea is far from rare in women—it just gets missed in them a lot more often. It’s estimated that nearly one in five women have the condition, but 90% of those who do aren’t aware that they have it. That major gap is due to both biological differences in how the condition shows up (in symptoms and test results), plus gendered dynamics that shape who seeks help—and gets taken seriously when they do.

Read on to learn about the unique signs of sleep apnea in women, the array of gender norms that create the perfect storm for underdiagnosis, and why it’s so important to seek care if you suspect this condition may be lurking beneath the surface.

The not-so-typical signs of sleep apnea in women make it easy for the condition to go undetected.

The classic profile of sleep apnea typically involves loud snoring, waking up choking or gasping for air, and excessive daytime sleepiness—as in, feeling like you could nod off at any moment, Andrea Matsumura, MD, a board-certified sleep specialist in Portland, Oregon, tells SELF. But in women, the symptoms can be a lot more subtle. “They tend to just feel like they’re fatigued, or as if something isn’t quite right, and experience irritability, headaches, anxiety, or depressed mood.” And in terms of nighttime signs? Women are more likely to point to frequent awakenings or restless sleep, Dr. Won says.

The reasons behind the differences aren’t totally understood, but research has surfaced a few theories. One is that people who menstruate get some protection against the worst of sleep apnea from the hormones estrogen and progesterone, “which support the soft structures of the back of the throat,” Dr. Matsumura says, “so the symptoms may not be as prominent.” (That changes with menopause—more on this in a sec.) Another explanation is that women have “a lower arousal threshold, meaning they’re more easily awoken,” Dr. Won says. So even a little snore or gap in breathing could be enough to jerk them into wakefulness, leading those with sleep apnea to spend the night tossing and turning—whereas “men may go longer with their airway obstructed without waking up,” Dr. Won says. The result? Men with sleep apnea may have more obvious snoring as they sleep, while women with the condition often struggle to stay asleep…and wind up feeling constantly unrested.

The resulting array of symptoms in women—insomnia, irritability, daytime fatigue—aren’t exactly dead giveaways for sleep apnea, so they may not push a doctor toward that diagnosis. After all, any number of other things (like stress, poor sleep hygiene, and mental health conditions like anxiety and depression) can mess with your ability to doze off and stay asleep at night, and leave you feeling like utter crap throughout the day.

It doesn’t help that a couple other key causes of daytime fatigue and sleep issues also occur specifically in people with female anatomy: pregnancy and menopause. It may be easy for a doctor to blame hormonal changes for things like mood swings, crankiness, insomnia, restlessness, and headaches in pregnant or perimenopausal folks, and in plenty of circumstances, they might be right. But that also means providers are more likely to overlook sleep apnea in these groups—which is doubly problematic, given that both pregnancy and menopause make you more susceptible to the condition. (The hormone fluctuations of pregnancy can trigger swelling in your respiratory tract that ups your risk for breathing issues at night, Dr. Won points out. Same goes for both the dip in estrogen and progesterone and the natural shift of weight toward the midsection during menopause, Dr. Matsumura says.)

The tools for screening and diagnosing patients for sleep apnea are also biased against women.

Even if a doctor suspects a woman may have sleep apnea, they still have to rely on tools for screening and diagnosis that might not offer an accurate result—because they were designed around the symptoms initially spotted in men. For example, take the main screening device for evaluating sleep apnea risk, the STOP-Bang questionnaire. It’s an acronym for eight questions (related to symptoms and demographics); each “yes” is a point, with higher scores linked to greater risk. “One of the questions asks if you’re a man, so you’re already minus a point if you’re a woman,” Dr. Matsumura points out.

The main test for diagnosing sleep apnea, called a polysomnogram or sleep study, may also fail to capture all cases in people with female anatomy because of some nuances around when in the night they tend to experience the condition. Research suggests women with the disorder usually have clusters of apneas, or pauses in breathing, specifically during rapid eye movement (REM) sleep, which is the key sleep stage when we consolidate emotions and process memories, Dr. Matsumura says, whereas men tend to have episodes more evenly across sleep stages. (That particular loss of REM in women with sleep apnea might also play a role in their greater experience of fatigue and irritability, she points out.) A polysomnogram involves getting hooked up to a bunch of sensors that track these apneas as you sleep.

But here’s the tricky part: A diagnosis of sleep apnea is currently based on your average number of apneas per hour throughout the night—more than five, and you have a mild form of the disease; above 15, and it’s considered moderate; and if you surpass 30, you’re in severe territory. REM sleep, however, is only about 20% of an eight-hour night, Dr. Won points out. So if women are usually just having apneas during REM (and not in non-REM), their average will be skewed lower.

“You could be having a hundred [apnea] events during REM sleep, but because it’s diluted by having none in non-REM, the end result looks ‘mild,’” Dr. Won says. And yet, experiencing a ton of apneas during REM can certainly leave you feeling fatigued and restless; plus, research suggests REM-related apneas, in particular, increase your risk for cardiovascular issues down the road (more on this below). The way REM-only apnea can get mischaracterized as NBD means that women—who, again, tend to have this type—may be denied insurance coverage for the treatment they clearly need, Dr. Won says.

Social factors related to gender just add to the problem of underdiagnosis in women.

It isn’t just biological differences and bias in medicine that cause sleep apnea to fly under the radar in women; it’s also cultural norms that might make it less likely for women to seek out care in the first place. That’s one reason why cis and trans women may both face disparities in diagnosis and treatment regardless of anatomical differences.

“It’s normalized in our society that women should be chronically sleep deprived and that we’re also supposed to suffer more,” Dr. Matsumura notes. “We start menstruating, and it’s like, ‘Well, you’re going to have cramps,’ and you might not sleep because of these hormonal changes. Or, ‘You’re pregnant, so it’s normal not to get good sleep.’ And then you have a baby, and it’s the same thing.” There’s also all the cultural messaging that equates womanhood with pain and inconvenience—whether it’s the suggestion that you jump through hoops to meet gendered beauty standards or that you should be willing and able to “do it all” (housework, family work, work work). It’s no wonder so many women pushing through fatigue might not suspect they could have a medical condition worthy of treatment.

Add to that the stigma surrounding the most well-known symptom of sleep apnea: loud snoring—which, reminder, can still be a sign in women, even if it’s less common. The harmful misconception that snoring is a “masculine” thing to be ashamed of might lead some women to avoid bringing up sleep apnea with their doctor. Research also suggests men who share a bed with a woman might be less apt to tell them about nighttime snoring or gasping (and suggest they seek care) versus the other way around, Dr. Won says. More proof of that point: Data show women are more likely than men to show up solo to doctor’s appointments for sleep apnea than with their bed partner.

It’s essential to check in with your doctor if you’re dealing with persistent daytime fatigue or other signs of sleep apnea.

Going undiagnosed with sleep apnea doesn’t just mean dealing with more fatigue, irritability, and restless nights (though that’s reason enough, in our book, to seek out care). It could also put you at greater risk for serious health issues affecting your heart and brain. Those little episodes of struggling for air trigger the release of hormones like adrenaline that stress your heart and ramp up your blood pressure over time, raising your chances of a cardiovascular event like a heart attack or stroke, Dr. Won says. And the dip in oxygen levels caused by apneas may also damage small blood vessels in your brain, putting you at greater risk of cognitive decline and perhaps even dementia. Not to mention the risks, more broadly, of getting consistently poor quality or insufficient sleep, like brain fog, mental-health issues, and a not-so-effective immune system, for starters.

All to say, if you feel like you’re never quite fully rested despite getting enough sleep, or you’re more groggy, irritable, or headache-y than usual, it’s worth bringing up sleep apnea with your doctor, especially if you identify as a woman or have female anatomy. This way, you can get to the bottom of what’s triggering your symptoms, sleep apnea or otherwise—and you can reduce your chances of going undiagnosed.

Related:

• The Truth About Popular Sleep Supplements, From Magnesium to Melatonin
• Is Sleep Apnea Genetic?
• 5 Things to Try If Sharing a Bed Is Completely Ruining Your Sleep

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