Is ovarian/cervical cancer hereditary?

My grandmother died of cervical cancer, and I heard that every other generation has a higher risk of hereditarily contracting a cancer. I have problems with endometriosis and ovarian cysts and I am afraid that it will lead to cancer on down the road. I get a pap every year, and so far, so good. I was a little concerned that a pelvic ultrasound came back showing that I had some free fluid in my pelvic area.