A prospective randomized parallel-group study was carried out to compare the efficacy of a single dose vaginal prostaglandin E2 gel with forewater amniotomy for induction of labour at term in 260 parturients (110 primigravid and 150 parous women) with low risk pregnancy and favourable cervix. In the prostaglandin E2 (PGE2) managed group, the primigravidae were treated with 2 mg PGE2 gel and parous patients with 1 mg PGE2 gel. Forewater amniotomy was performed 4 h later, or sooner if women requested analgesia. In the amniotomy group, artificial forewater amniotomy was carried out and a repeat cervical assessment done 4 h later, or sooner if women requested analgesia. In both groups, intravenous oxytocin was established if there was evidence of disordered uterine activity, 6 h after the start of initial intervention. An assessment of consumers' views was carried out by using a standardized questionnaire completed 48 h after delivery. There was a significant reduction in the requirement for oxytocin augmentation in women treated with PGE2: primigravidae, odds ratio (OR), 0.27 and 95% confidence interval (CI), 0.12-0.61; multiparae, OR, 0.19 and 95% CI, 0.08-0.45. Fewer primigravidae managed with PGE2 gel required epidural analgesia (OR, 0.16; 95% CI, 0.06-1.00). Fewer parous women managed with PGE2 gel required parenteral opiates (OR, 0.44; 95% CI, 0.23-0.85) and more women required inhalation analgesia or no analgesia (OR, 2.22; 95% CI, 1.76-2.79). The intervention to delivery intervals were shortened in PGE2 groups independent of parity but the differences were not significant.(ABSTRACT TRUNCATED AT 250 WORDS)