After educating a 19-year old client about possible adverse effects of her oral contraception, which of the client's concerns shows a lack of understanding?

Ovarian cancer is not an adverse effect of taking oral contraceptives. Some studies have shown a reduction in ovarian and endometrial cancers when using birth control pills. Some side effects of oral contraceptives are weight gain, breast tenderness, nausea, headaches, breakthrough bleeding, and thrombophlebitis.