If you can afford it and don't have anyone else suitable, absolutely. I would not want to be without one.

I had birth helpers/support people for my home births, but DH and DD only for Angus' birth coz DH didn't call anybody on our list!!

Your mum, sister, close friend, or anyone you know who you think is up to the job and who you feel comfortable with. A woman who's recently had a baby herself, or a student midwife or doula you feel comfortable with.

It's tiring for hubbies/partners, and there's so much to do. You need someone to feed and water you, encourage you, tell jokes, make phone calls, give partner a break, hold your hand, get you hot/cold wash cloths, tie your hair back, hold the bucket while you puke, fetch the midwife, adjust your pillows, change the CD, tell you you're doing well, hold the camera, rub your back, put some balm on your lips.......

The midwife may not be there the whole time, and has medical stuff they need to do, and all the little things no-one thinks of can help so much.

Yay for doulas! You've got to be on call in the middle of the night though!