I think it's okay for a baby, sure. I do think it is a little passé à la Deborah, but certainly not problematic.I would certainly recommend the much fresher Dinah (DYE-nuh), which is adorable and underused. LoveDinah.
Know what's weird? My husband has an Aunt Diana, but she pronounces it DIE-a-na so it sounds really close to Dinah. I thought her name was Dinah for awhile.I've always wondered why Dinah wasn't more common. It's such a sweet little name.
I've wondered this too. Perhaps it's because Dinah is featured in that American folk song, "I've Been Working On The Railroad." I've only known one girl named Dinah when we were in high school.