Prostate cancer patients often experience a greater degree of male incontinence than they expect, a study has found.

Researchers at the University of Michigan's urology department surveyed 152 men, all of whom underwent surgery for prostate cancer.

Participants were given extensive counselling before undergoing surgery to prepare them for possible complications, including male incontinence.

They were asked about their expectations prior to surgery, and surveyed again one year after their operation.

Study authors found that many men's urinary incontinence was worse than they had expected.

Forty-seven per cent of patients said their male incontinence was worse than anticipated, while just 12 per cent had lower incontinence levels than expected.

Writing in the Journal of Urology, the study authors concluded that men often have "unrealistic expectations" of urinary function after prostate cancer surgery, despite receiving advice prior to their operation.

Daniela Wittmann, sexual health coordinator at the University of Michigan, told Reuters news agency that experts cannot predict the degree of male incontinence that an individual will experience.

"Which means that, if in doubt, people tend toward being hopeful and optimistic," she added.