I did it for my first. About 10 min from 36ish weeks onwards every night. I used olive oil I think. Birth was good, a tiny tear that didn't need any stitches. The massage helped me know what feeling to expect when Caty's head was crowning which was helpful.

No massage for #2 and no tears (waterbirth probably helped!).

I second webbmeg's praise of pelvic floors. I'd say they're more important than massage too.