What is the song that has an eerie female voice singing ah-a-a-a-a-a-a in one part of it?

This song has been stuck in my head for the past few days. Midomi can't recognize it when I hum it. I was hoping someone could help me out. I think it is from either the 80's or early 90's, and it is a hit (I have heard it on a hit radio station). Seems like the notes could be BAGABAG...