PCOS is associated with a higher risk of endometrial cancer due to constant estrogen stimulation and lack of progesterone.

“but in PCOS because you're not ovulating and those ovaries each little follicle makes a tiny amount of estrogen we'll say each little follicle when it's not responding will make you know one to two peagrams of estrogen but if you have 50 of them each month you're having some constant estrogen exposure so that lining of the uterus is being constantly stimulated to grow and you're never getting the progesterone to stabilize or the progesterone withdraw to bleed so endometrial cancer is much higher in people with PCOS who don't ovulate”