Wilson P D
Br J Obstet Gynaecol. 1978 Dec;85(12):941-4. doi: 10.1111/j.1471-0528.1978.tb15858.x.
A comparison was made between four methods of ripening the unfavourable cervix (extra-amniotic prostaglandin E2 gel, oral prostaglandin E2, intravaginal prostaglandin E2 and intravenous oxytocin) in a clinical trial involving 60 primigravidae. In all groups there was an improvement in cervical status. This was significantly greater in those patients who received extra-amniotic prostaglandin gel and they also showed significant decreases in the mean induction-delivery interval and in the incidence of Caesarean section.