Everyone's biggest fear when stepping in a doctor's office is coming out with an illness they never knew they had.
One of my friends had been complaining of intense stomach pain for months. She visited the doctor regularly to get blood work and was on stress pills for quite some time. She even got an endoscopy, where they inspected her stomach from the inside to see if there was anything wrong.
They discovered nothing.
After months of what she described as pure agony, my friend was referred to a gynecologist, who shed some light on what's been going on.
Turns out it wasn't her stomach that wreaking havoc on her health, it was her baby making parts.
According to the American College of Obstetricians and Gynecologists, anyone who has their period is at risk of developing a condition known as endodemitriosis.
It's estimated that 1 in 10 women have it, and they may not even know they do. Some women show obvious signs, like my friend, and others may not show any signs of the condition at all.
Some celebrities have been coming forward to speak about their personal struggle to raise awareness about this condition.
Dancing with the Stars dancer Julianne Hough recently opened up to E! News, revealing how she has been suffering "in silence."
Singer-songwriter Halsey also has been suffering with the condition for years, saying she has had to go "backstage in the middle of my sets, or fighting back tears on an airplane, or even being in so much pain [that she] would vomit or faint."
Scary stuff. Here's all you need to know about this mystery illness: