Comedian Amy Schumer has revealed her longtime health struggles with endometriosis, noting it is a "lonely disease." Schumer made the comments during an episode of the Paramount+ docuseries "The Checkup With Dr. David Agus." A brief clip was posted online before the episode's air date Tuesday. "I've been in so much pain, you know, my whole life — not just the week of my period; it's [also] during ovulation," Schumer said."I would hopefully get a good week a month where I wasn't in pretty significant pain, [but] still trying to achieve, still trying to go through life. It's been really difficult." Endometriosis is a chronic disease that occurs when "tissue similar to the tissue that normally lines the inside of your uterus — the endometrium — grows outside your uterus," according to the Mayo Clinic. The disease, which affects hundreds of thousands of women across the world, can cause severe pain. AMY SCHUMER SAYS OSCARS JOKE LED TO DEATH THREATS Last year, Schumer was treated for the disease with a hysterectomy and had her appendix removed because of a tumor created by endometriosis. Before the treatment, Schumer had noticed the severe pain but was unaware of the cause. "It's really a lonely, lonely disease," the 41-year-old celebrity said. "It was just this pain you can't see. And, you know, there is the inclination to always think a woman is just being dramatic. CLICK HERE TO SIGN UP FOR THE ENTERTAINMENT NEWSLETTER "You tell someone you get really bad cramps, and they’re like "Oh, well, being a woman …' And you're like, 'No, it's irregular.'" Schumer says that, after receiving treatment, her life has changed, and she feels like a "different person." "It just felt like someone lifted this veil that had been over me. And I just felt like a different person, like, a new mom," Schumer concluded. "If the trade-off is that you will have a little scar on your belly button and one right next to it … I think scars are cool."