No! Doulas do not replace the father's role in any way. A Doula is there to relieve back pain and observe tension in other areas of her body. The father is there face-to-face, holding hands, and giving emotional support to his wife. Doulas can take the pressure off of the fathers, which allows them to do what they do best- to love their partner.
Some fathers have a hard time remembering what was taught in class, and often were not prepared to see what labor and birth was really like. A study performed by S.M Copstick, et al, published in the Journal of Psychosomatic Research reported that "women were unlikely to use techniques learned in childbirth classes beyond early labor unless their partners were trained & willing to help coach them." Doulas can remind fathers how to help the mother & be there for her.
Birth can be a scary thing for first time fathers. Doulas can also reassure the father that everything is happening as it should. In fact, many fathers have said that having a doula present made them feel less anxious and were better able to enjoy the birth.
Sweet Pea in the Pod