It describes a sharp ovulation pain on one side of your lower abdomen that occurs once a month around the time your ovary releases an egg into your fallopian tube.
In fact, it's so common that about one in five women experience it on a monthly basis, says Nicole Scott, M.D., an ob-gyn at IU Health.
So what is it? Technically the word is German for "middle pain," and it describes a sharp ovulation pain on one side of your lower abdomen that occurs once a month around the time your ovary releases an egg into your fallopian tube, according to the Mayo Clinic. That's right, some women can feel when they release an egg.
"It is a real phenomenon and in my experience it's fairly common," Scott says. "But not all women experience it, and some women may experience it to different degrees than others."
Eggs can be tricky things. As a woman, you were born with about two million eggs (technically, they are immature eggs called "follicles") and that is all you will ever have.
Unlike men, who continuously create sperm throughout their lives, eggs are a limited supply. While it varies from woman to woman, 95 percent of women will have less than 12 percent of their eggs left by age 30, according to a studypublished in PLoS ONE. By age 40, that number is down to 3 percent. This means you lose about 8,000 eggs per month(!!!) and once they're gone, usually between ages 40 to 50, they're gone, and you're infertile.
During your fertile years, each month one egg ripens in one of your ovaries and roughly two weeks before your period starts, the ovary sends a signal to your brain that it's time to pop the egg out, Scott explains.
And "pop" really is the right word for it. "The egg is released from a developing follicle or cyst in the ovary, but because there are no openings in the ovary the egg actually bursts through," she says.
While that definitely sounds painful—bursts?—most women don't feel a thing. But those with mittelschmerz report feeling a sharp, short pain, sometimes accompanied by a lingering aches on the side from which the egg was released. It's a totally normal experience and it doesn't mean anything is wrong, Scott says. What's more, while some women feel it every month, on alternating sides of the body, others only feel it every couple of months, and always in the same side. That's because your two ovaries take turns releasing their eggs.
However, there is an upside to ovulation pain: If you're tracking your fertility, knowing exactly when you ovulate can help you be more accurate in identifying your fertile days and predicting your next period. Think of it like your secret, slightly strange superpower?
Because ovulation pain is typically brief and mild, you don't need to do anything for it, but if you're feeling particularly achy, it's fine to take ibuprofen, Scott says. Some women find relief with hot or cold packs. There are a small number of women who find mittelschmerz to be extremely painful and say it interferes with their lives. So if the pain is really disruptive and tests can't find any other reason for it, birth control pills can prevent ovulation and, therefore, mittelschmerz, she explains.
Not all mid-cycle abdominal pain is ovulation pain, however. Things like ovarian cysts, fibroids, scar tissue, cancer and a life-threatening ectopic pregnancy can sometimes cause similar pain at first. The difference is that those will often cause pain that increases in intensity and duration. If your pain is not 14 days before your period or lasts longer than three days, it is probably not related to ovulation and you should consider other causes she says, adding that if the pain lasts more than two weeks, it's time to call your doctor.
In the meantime, mittelschmerz makes for a good party trick. Imagine being the girl who can say, "And I just dropped an egg... now!"