The purpose of this stratified randomized trial was to determine the physical and psychological effects of continuous, one-to-one professional support on childbirth outcomes. Data were gathered during prenatal and postpartum interviews with, and from the medical records of, 103 low-risk women. All subjects had attended one of two types of prenatal education programs, were accompanied by husbands or partners during labor, and had vaginal deliveries. Subjects in the experimental group were less likely to have medication for pain relief and less likely to have episiotomies. Three variables were found to predict perceived control during childbirth--expectations of control, the presence of a continuous professional caregiver, and pain medication usage. The results demonstrate the importance of the traditional nursing support role during childbirth.