Last updated: Jun 13, 2016

Former Olympic gymnast Shannon Miller is celebrating five years free of ovarian cancer by spreading awareness about the easy-to-miss symptoms of the disease.

Ovarian cancer is the deadliest form of female reproductive cancer. The American Cancer Society (ACS) estimates that in 2016, more than 22,000 women will receive a new diagnosis and more than 14,000 women will die from the disease. 

When ovarian cancer is caught early, an overwhelming majority of patients94%live longer than five years, according to the ACS. But the trouble is, only 20% of ovarian cancers are found early.

In most cases early cancers don't cause any symptoms. And when they do, the symptoms—including abdominal pain or discomfort, abdominal swelling or bloating, weight loss, and urgency in urination—may be confused with other illnesses, says Linus Chuang, MD, a professor of obstetrics, gynecology, and reproductive science at the Icahn School of Medicine at Mount Sinai in New York City.​

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Before her diagnosis, Miller had been experiencing severe stomachaches and bloating. She had also lost six pounds. But as she told People, she blamed her discomfort on her period, and assumed the change on the scale was due to baby weight melting off after the birth of her son (Rocco, 6). 

Luckily Miller's doctor found the cyst on her ovary right away. Miller's treatment included surgery and chemotherapy, and now the 39-year-old gold medalist says she thanks God every day that she's here. She's also speaking out to encourage other women to heed the early warning signs that she nearly missed.

So what are the clues that your abdominal or urinary symptoms could be something more serious? As Dr. Chuang puts it, they "are more common in frequency, worsen progressively, and recur more frequently." If your symptoms are persistent or worsening, seek gynecologic care, he urges.

Screening for ovarian cancer may include a pelvic exam and imaging tests, as well as a blood test to detect levels of a protein found on ovarian cancer cells called CA 125.

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Miller is now a spokesperson for a company that developed another blood test called OVA1, which helps doctors determine if a pelvic mass is cancerous, and whether surgery is necessary. She wants women to visit KnowPelvicMass.com to get more information about early detection. 

"I was lucky my doctors caught [my cancer] early," Miller told People. "But I don't want other women to count on luck."