 Participants will then be randomised in a 1:1 ratio to either 1 synthetic osmotic cervical dilator or 2 a 10-mg controlled-release dinoprostone vaginal insert. Randomisation will be provided by a computer generated programme. A research assistant discloses the nature of the assignment only after enrolment. Investigators have calculated that 860 patients 430 in each arm will need to be recruited over a 2 year period. Given the nature of the intervention, the SOLVE trial will not be a blinded trial. 