List Of Birth Control With My Health Insurance Blue Cross?

This whole thing is kind of confusing... I have blue cross with blue preferred plan with my husband. I'm wondering if they have a list of BCs. I checked the list showing level two prescriptions and Yaz was on their but no other BCs were on any other pages. But then I saw Viagra on the list that should be precertified but it wasn't on the other list. Well I guess what I'm trying to get at is, is there any list for me to find out what BCs are an option for me?