Peyronie’s disease occurs when scar tissue forms inside your penis and causes your erection to curve. It can make erections and sex painful.
Doctors aren’t sure what causes Peyronie’s disease. But they think it develops when small blood vessels inside your penis rupture during sex or athletic activity, or if you get injured. As your penis heals, it forms scar tissue that leads to Peyronie’s disease. Not all men with penile scar tissue develop the disease, so experts think genetics might be a factor, too.