I had a doula for my sons birth and it was the best decision I made. When I got to the hospital, I was really nervous but as soon as she walked in the door, the atmosphere changed. She popped on some mediation music, started burning lavender oil and massaging my feet to calm me down. She helped me get through each contraction and she gave me strength to go on. She was amazing!
Midwives won't be with you every second of your labour. They come in and check on you. The benefit of having a doula is that she's with you the entire time, helping you through it and making sure you're comfortable. She's there to give you physical and emotional support.