Subjects of a study by O’Brien et al. (A-37) consisted of 100 low-risk patients having well-dated pregnancies. The investigators wished to evaluate the efficacy of a more gradual method for promoting cervical change and delivery. Half of the patients were randomly assigned to receive a placebo, and the remainder received 2 mg of intravaginal prostaglandin E2 (PGE2) for 5 consecutive days. One of the infants born to mothers in the experimental group and four born to those in the control group had macrosomia.