A randomized study was performed to compare three methods of labour induction in 143 clinically normal women (43 nulliparas) at term: amniotomy with or without intravenous oxytocin, extra-amniotic prostaglandin (PG) E2 gel, and extra-amniotic PGE2 gel plus an indwelling catheter. The three methods appeared to be comparable in effect and all of them were perinatally safe. Thus, if preference is given to keeping the ovular sac intact during the early phase of induced labour, extra-amniotic PGE2 in viscous gel, either with or without an indwelling catheter,. can replace the classical induction technique.