Recently, Girls star Lena Dunham took to Instagram to talk to followers about the pain she regularly experiences due to endometriosis. And despite the fact 13.6 million in the U.S. suffer from mild to severe endometriosis on a frequent basis, the posts were initially met with confusion and a lack of awareness.

Indeed, according to WomensHealth.gov, endometriosis isn’t something that many are aware of.

So what is endometriosis exactly? It is a disease that affects a person during menstruation, causing moderate to severe pain and discomfort. Typically, menstruation pushes cells out of the uterus. But for those with endomtriosis, the cells inside of the uterus continue to grow within the pelvic cavity, creating blockage in the fallopian tubes.

As a result, those with endometriosis experience painful periods, ovarian cysts, and infertility. In fact, it’s one of the leading causes of infertility in the U.S.

In rare cases, endometriosis can also result in uterine cancer, a disease that a disproportionate of Hispanic patients die from, as they are typically diagnosed with more aggressive, less treatable forms of the cancer.

Luckily, endometrial uterine cancer is not always linked to endometriosis. Additionally, endometriosis can be manageable if treated properly. There are three main ways to treat endometriosis: laparascopy, birth control, or the ingestion of a drug called Lupron. While all three options are viable, most medical professionals recommend birth control, as it is the most sustainable means of managing endometriosis.

“I think the easiest treatment is the birth control pill, and it also often helps with eliminating the pain from periods, a common symptom of endometriosis,” says Dr. Jane Frederick, a board-certified endocrinologist and infertility specialist.

Regardless of what treatment patients choose or their plans for the future, it is important to diagnose and treat endometriosis as early as possible.

“It’s very treatable and I encourage women to read more about it,” Dr. Frederick concludes.