Doctors thought this teen was pregnant — but she actually had a rare disease

How could a man go more than 20 years with such severe constipation? The answer is Hirschsprung’s disease. (iStock)

A 17-year-old girl from Bowling Green, Ohio, is speaking out about her experience with ovarian cancer to let women know that the disease can happen to young people, too.

Caly Bevier tells People that she first developed symptoms in 2015 when her stomach became bloated, she started vomiting, and just felt lousy. At first, her doctor thought she was pregnant. “She said the only other thing it could be is a tumor on your ovaries, and I said, ‘That’s what it has to be then,’” Caly said.

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She spent three months in and out of the hospital and had 21 chemo infusions. She’s now been in remission for two years.

“I kept telling myself to just be positive,” she said of her health battle. “I knew everything would be okay in the end. When you’re going through something so hard you realize how important all the little things in life really are. It has changed me”

Now, Caly wants to make people more aware of the signs of ovarian cancer. “I had a lump growing in my stomach for a year and I just ignored it. I didn’t really think anything of it because it wasn’t a problem,” she told People.

It seems crazy that someone Caly’s age would develop ovarian cancer, an illness that typically impacts older women, but women’s health expert Jennifer Wider, M.D., says it’s possible—it’s just very rare.

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The problem with ovarian cancer is that the symptoms are often vague, Wider says, so people often don’t realize something is wrong early on. Ovarian cysts are often asymptomatic, Wider says, but symptoms can include abdominal discomfort, back pain, bloating, changes in appetite, changes in bowel habits, nausea, indigestion, and weight loss.

Again, it can be tough to spot the symptoms of ovarian cancer early on, but Wider says if you’re losing weight for no apparent reason and have a change in your bowel habits and appetite, it’s worth flagging your symptoms to your doctor. Ovarian cancer also can be genetic, so know your family history and mention it to your doctor if you experience symptoms.

This article first appeared on Women's Health.