Nothing is worse than waking up drenched in the middle of the night, sweating as if you’ve just run a marathon, and needing to climb out of bed to change your pajamas before you try to drift back to sleep.

But that’s exactly what 10 to 60 percent of the population experiences each year, according to research published in the Journal of the American Board of Family Medicine.

Night sweats are pretty common and while they can be a red flag, “for the vast majority of people, don’t represent a medical concern,” reports the Mayo Clinic. But they are annoying, and if you’re one of those people that experiences night sweats, you may be asking yourself: “Why do I sweat so much at night?” We looked into the research and asked the experts — and the answer may surprise you. (Hint: it’s not always a menopause thing.)

Night sweats can occur due to a variety of reasons. Ahead, here are some of the most common reasons you may be sweating so much at night.

OK, we’ll get the condition most commonly associated with night sweats out of the way first: hot flashes. But that doesn’t always mean menopause. Hot flashes can occur at any time during your menstrual cycle — day or night — and not just during menopause.

“Any hormone event that causes a significant decrease in estrogen affects the body’s thermostat in the hypothalamus, which controls body temperature and can lead to hot flashes,” Sherry Ross, MD, an ob-gyn at Providence Saint John’s Health Center in Santa Monica, CA, tells POPSUGAR.

While estrogen decreases leading up to menopause, it can also dip like clockwork during your monthly cycle, typically around the first day of your period and a few days prior to that.

Other hormonal imbalances can also cause night sweating, explains Kristine Arthur, MD, an internist at MemorialCare Orange Coast Medical Center in Fountain Valley, CA. These include hyperthyroidism or adrenal disease, which occur when the body doesn’t produce enough cortisol or aldosterone.

So, while your monthly cycle may be to blame for periodic night sweats, if you find it happens more frequently, it’s worth making an appointment with your doctor to rule out other causes. “Both of these conditions can be detected with blood and urine testing in your doctor’s office and successfully treated with medications or other treatments,” Dr. Arthur tells POPSUGAR.

Low blood sugar (or hypoglycaemia) can be another culprit of night sweats, and is common among people with diabetes. It can happen while you’re asleep causing you to “wake up during the night or cause headaches, tiredness or damp sheets (from sweat) in the morning,” according to the United Kingdom National Health Service (NHS).

If you have other symptoms of diabetes, such as increased thirst, frequent urination, or sweet-smelling urine, consider visiting your doctor to get checked out.

Certain medications, like antidepressants, can also result in night sweats, Dr. Arthur says. Other meds like drugs used to treat low blood sugar with diabetes (hypoglycemic agents) and hormone therapy can also cause you to wake up feeling drenched, per the Mayo Clinic.

If you’ve started a new medication recently, it’s worth asking your healthcare provider if it’s associated with night sweats, and if there’s anything you can do to alleviate the symptoms.

In some cases, night sweats can even be a sign of infection. “For example, if you’ve recently been ill with a minor respiratory infection, a slight fever can cause you to sweat more at night, as your body’s normal day/night temperature reset may be exaggerated,” the Mayo Clinic reports.