Is having to urinate a minimum of every three hours considered frequent urination ? i don't recal what has been normal for me. ovarian cancer ???

Yes it may be: Frequent urination means having to run to the bathroom even when your bladder is not full of urine. It is usually a combination of frequent urination(for small quantities) and urge to rush to the bath room which implies bladder infection. This can be verified with a urine test(called Urinalysis/UA). Ovarian cancer is less likely unless you have swelling of your abdomen?