A 29-year-old G2P1 at 39 weeks of gestation with a history of one previous vaginal delivery is admitted for induction of labour due to gestational diabetes mellitus. On examination, the cervix is 3 cm dilated, 90% effaced, soft in consistency, and the fetal head is at 0 station. Fetal heart rate is 140 bpm with normal variability. The patient has no contraindications to labour. After confirming fetal well-being with a 20-minute cardiotocograph, oxytocin infusion is started at 2 mIU/min. After 4 hours of oxytocin, the patient has had 3 contractions in 10 minutes, each lasting 45 seconds. The cervix remains at 3 cm dilation. What is the most appropriate next step?