A randomized controlled trial was carried out to evaluate the extent to which a program of reinforced pelvic floor muscle exercises (PFME) reduces urinary incontinence 1 year after delivery. Two hundred and thirty women who were incontinent 3 months postpartum were randomized to either a control group doing standard postnatal pelvic floor muscle exercises (n = 117) or to an intervention group (n = 113) who saw a physiotherapist for instruction at approximately 3, 4, 6 and 9 months postpartum. Results collected 12 months after delivery included prevalence and frequency of incontinence and PFME, sexual satisfaction, perineometry measurements and pad tests. Twenty-six (22%) of the control group and 59 (52%) of the intervention group withdrew before the final assessment. The prevalence of incontinence was significantly less in the intervention group than in the control group (50% versus 76%, P=0.0003), and this group also did significantly more PFME. There were no significant differences between the groups as regards sexual satisfaction, perineometry measurements or pad test results.