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Women whose pelvic floor has become weakened, for example through pregnancy and childbirth, benefit from pelvic floor muscle training. Specific exercises can strengthen muscles and improve bladder control. Women are sometimes offered a biofeedback device which allows them to see their muscles working as they exercise. But new research found that the device offered no benefit over the exercises alone.

The study included 600 women who had urinary incontinence. They all followed a supervised programme of pelvic floor muscle training, and were asked to continue the exercises at home. Half the women were given a biofeedback device which displayed on screen the electrical activity in their pelvic muscles as they performed the exercises in clinic and at home.

Two years after treatment, all women had reduced symptoms of incontinence. But there was no meaningful difference between the two groups. The study concluded that the biofeedback device provided no additional benefit. It was not a cost-effective addition to pelvic floor muscle training. 

The researchers say that biofeedback should not be routinely offered alongside pelvic floor muscle training. 

Further information on pelvic floor exercises is available on the NHS website.

What’s the issue?

Pelvic floor muscle weakness reduces bladder control in women and can result in urinary incontinence. It is often associated with pregnancy and childbirth, and is estimated to affect one in three women worldwide. 

Regular pelvic floor muscle exercises, as part of a supervised program, can strengthen the pelvic floor muscles, improve bladder control, and relieve the symptoms of urinary incontinence. The NHS spends about £38m each year providing these programmes. However, some women continue to have incontinence after treatment, and there is growing interest in how to make programmes more effective, and more cost-effective.

One possibility is using a biofeedback device to show women the electrical activity in their pelvic floor muscles when they perform the exercises.  This biofeedback (electromyography or EMG) could motivate women to exercise more intensively and for longer, with a better technique. It was thought it might therefore improve bladder control further than the exercises alone.

Some studies show biofeedback offers extra benefit and has an impact on incontinence. But this could be the result of extra contact with health professionals when women use the devices. This study is the first to address this possible source of bias: both groups had equal contact with professionals, and women used the biofeedback device at home. It aimed to tease out the true impact of biofeedback.

What’s new?

The study followed 600 women with urinary incontinence, treated at 23 different UK centres. They were all offered a supervised programme of pelvic floor muscle exercises: six face-to-face appointments with a therapist over 16 weeks. They were expected to practise the exercises outside of these sessions. In addition, half of the women were given an EMG biofeedback device to use in clinic and at home.  

After two years, the study compared the severity of the women’s urinary incontinence and looked for differences between the two groups.

    • Women’s symptoms of urinary incontinence improved by a similar amount in both groups. Severity scores were reduced (from 12.5 to 8.2 with biofeedback and from 12.3 to 8.5 without). The small difference between the groups was not meaningful and suggests the biofeedback offered no additional benefit. 
    • The similarity between groups was seen at various time points – not just at the end of the study.
    • Other outcomes (such as symptoms in the urinary tract, further treatment for incontinence, bowel symptoms, quality of life related to incontinence) were similar between the two groups.
    • There were no serious complications in either group, but more women (21) who had received biofeedback had a complication that could have been related to the intervention (compared to the two women who had the exercise programme alone).
    • The addition of biofeedback was not significantly more expensive than the exercises alone.

The researchers interviewed some of the participants. Women in both groups were positive about the intervention they had received. They  particularly valued the input of therapists. 

There were differences within groups about how much exercise the women said they carried out. A desire to improve their continence, confidence in carrying out the exercises and an expectation of how they would benefit, helped them continue with the exercises in the short- and long-term. Barriers included a lack of time, ‘life taking over’ and other health problems. 

Why is this important?

EMG biofeedback is a relatively simple technique that can be added to pelvic floor muscle exercise programmes. A Cochrane review (a high-quality review of existing evidence) suggested in 2011 that biofeedback ‘may provide benefit’. The Review stated that it was unclear whether the benefit was from the biofeedback itself or from  extra contact with staff. Even so, many therapists now recommend biofeedback. 

The new study challenges this practice. It suggests the benefit of biofeedback seen previously was due to increased contact with health professionals. The study concludes that there are no grounds for routinely adding biofeedback to pelvic floor muscle training. The technique does not improve the severity of continence after two years and is unlikely to be cost effective.

What’s next?

NICE guidelines published in 2019 already recommend that EMG biofeedback should not be routinely offered to women as part of pelvic floor muscle training. Commissioners should therefore not provide it as standard care.

Biofeedback is still recommended for women unable to contract their pelvic muscles. These women were excluded from the study. Future work could explore whether biofeedback is actually effective and should continue to be recommended for this group. 

The researchers expect that when the 2011 Cochrane review is updated, it will incorporate these results. They will also feed into an evidence review due next year from the International Consultation on Incontinence

Although the biofeedback device used in this study provided no additional benefit, other techniques might. It is possible that newer devices could be effective and could be studied further. More research is also needed on how additional support offered by health professionals can improve the results of the exercise programmes and make them more cost-effective.

You may be interested to read

This NIHR Alert is based on: Hagen S, and others. Basic versus biofeedback-mediated intensive pelvic floor muscle training for women with urinary incontinence: the OPAL RCT. Health Technology Assessment 2020;24:70 

The Pelvic Floor Muscles - a Guide for Women: Information from the Pelvic Obstetric and Gynaecological Physiotherapy, a professional network affiliated to the Chartered Society of Physiotherapy. 

Summary of the NICE guidelines on managing urinary incontinence in women

Your pelvic floor: A video from NHS Highland in conjunction with the Association for Continence Advice (ACA). 


Funding: This project was funded by the NIHR Health Technology Assessment programme. 

Conflicts of Interest: Several authors have received fees and funding from various pharmaceutical companies and law firms, outside of this work.

Disclaimer: NIHR Alerts are not a substitute for professional medical advice. They provide information about research which is funded or supported by the NIHR. Please note that views expressed in NIHR Alerts are those of the author(s) and reviewer(s) and not necessarily those of the NHS, the NIHR or the Department of Health and Social Care.

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Study author

The previous evidence was contradictory, and I was genuinely unsure what the outcome of our trial would be. It had a sound theoretical framework, with both groups of women receiving the same intervention (pelvic floor exercises) other than the addition of the biofeedback. I was confident that the trial was a fair test of the additional benefits of biofeedback. I was surprised how consistent the findings were – it didn’t matter which outcome measure you looked at, none showed any evidence of a difference between the groups.

The NICE guidelines were published in 2019, and the evidence should already be being implemented in the UK.  It would be interesting to survey the 23 centres who took part in the trial – I hope their practice has now changed as a result.

Suzanne Hagen, Deputy Director of the Nursing, Midwifery and Allied Health Professions Research Unit, Glasgow Caledonian University

Specialist Physiotherapy Network

Urinary incontinence continues to be a problem for women at many points in their lives. It is recognised that they delay seeking help and may receive very variable levels of information, support and treatment. Understanding what interventions work best is a necessary addition to providing women with evidence-based effective interventions that allow them to get on with their lives. 

Previous research has indicated that specialist physiotherapists delivering an intensive intervention is effective. Understanding the optimal components of an intervention will help refine this treatment and improve effectiveness.

OPAL has challenged the evidence to date with a well conducted pragmatic study  providing useful additional knowledge and evidence for optimal management of urinary incontinence.

Importantly women who could not contract their pelvic floor muscles were excluded. In routine practice these women are more likely to be offered biofeedback and neuromuscular electrical stimulation as part of a physiotherapy treatment programme. The lack of additional benefit of biofeedback in this trial reinforces the importance of the therapeutic relationship between a patient and healthcare professional. This should be reflected in the future planning of services to ensure that face to face time is not reduced.

The process evaluation provided useful additional data about the adoption of optional add-ins. More work is required to understand how behavioural change techniques and information motivation behavioral skills can be learnt by physiotherapists and added to existing programmes.

Kate Lough, Chair, Pelvic Obstetric and Gynaecological Physiotherapy (POGP), a professional network affiliated to the Chartered Society of Physiotherapy

Lived Experience

This could have a very significant impact. Women are desperate to improve their continence and biofeedback is thought to be better than exercises alone. But it is the exercise programme itself, and checking that the exercises are being correctly carried out, which appears to make the difference. 

All women need physiotherapy after giving birth to reduce the chance of urinary incontinence. One-to-one face-to-face contact with a physiotherapist would ensure the exercises are done and are done correctly. Perhaps our commissioners should look at postnatal care in France. There women get six weeks’ physiotherapy after giving birth, and it is extended to ten weeks if the pelvic floor is still an issue. 

It would be good to increase public awareness of the interventions available. Pelvic floor training is helpful before pregnancy too. Young adults in secondary school would benefit from learning to use their pelvic floor correctly. Since biofeedback is not necessarily any better than exercises, it may be easier to get the public health message across.

Jacqueline Emkes, Public contributor, Bedford 

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