A common surgery to treat vaginal prolapse using an artificially grafted mesh has more problems than benefits, our Cohrane review has found. Women who underwent the operation had high rates of needing repeat surgery due to mesh exposure, bladder injury and urinary incontinence.
A vaginal prolapse occurs when the walls of the vagina become weak and collapse inwards. Women can feel a lump or bulge low in their vagina, which is exacerbated at times of physical activity. The debilitating condition affects up to 50% of women who have had children.
We evaluated the safety and success of inserting mesh through the vagina (transvaginal) with that of traditional surgery that repairs damaged tissue. The aim was to provide clarity in a long-standing controversy over vaginal prolapse treatment.
Complications following transvaginal mesh surgery have led to lawsuits in the United States and to Scotland’s health minister temporarily suspending the technique in 2014 pending safety investigations.
We analysed evidence from 37 randomised trials in 4,032 women and found 12% of those who had mesh inserted suffered from the mesh being exposed in the vagina. This can cause vaginal bleeding, pain, painful intercourse and penile scratching or bleeding in the male partner.
While 7% more women who had transvaginal mesh surgery compared to a native tissue repair reported successful resolution of prolapse, one in 12 of these needed repeat surgery for mesh exposure.
Newer transvaginal mesh products available in Australia haven’t been rigorously evaluated despite being on the market for at least five years. We advise clinicians ensure women understand this uncertainty, as well as the proven complications, before undergoing the interventions.
Pelvic organ prolapse
Overweight women, those with a family history of the condition or who chronically strain, by coughing, constipation or heavy lifting, are at increased risk of vaginal prolapse.
Women with the condition can experience incomplete emptying of their bladder or bowel and feel very negatively about their body, which impacts sexual function.
As many as 10% to 20% of women with vaginal prolapse will need surgery.
Until the early 2000s, surgeons used different techniques to treat prolapse involving stitching the damaged tissues surrounding the vagina. These remain relatively successful, but rates of recurrent prolapse of up to 30% have been reported.
Following successes incontinence surgeons have had using tapes to support the urethra like a sling and others using mesh in hernia repair, gynaecology surgeons adopted the use of the net-like mesh to support the vagina.
The technique took off and in 2010, transvaginal mesh operations accounted for nearly 25% of prolapse interventions in some countries.
In the last few years, increasing complaints from women who had undergone transvaginal mesh surgery have raised questions about the safety of the procedure. The problems included vaginal pain, painful intercourse and vaginal bleeding, secondary to the mesh rubbing or becoming exposed in the vagina.
Although there has been insufficient evidence as to the frequency of the complications, as well as no consensus on the best approach to treat the condition, regulatory authorities in several countries took some action.
In 2012, the United States Food and Drug Administration (FDA) reclassified transvaginal mesh as a high-risk device that demands a higher level of evaluation of new products. Existing mesh devices were also required to report greater comparative data to determine their efficacy and safety. To date, these evaluations have not been published.
The Medicines and Healthcare products Regulatory Authority (MHRA) in Britain recently reported “a strong disparity between the types of experience patients are reporting and the published evidence” relating to transvaginal mesh. The MHRA recommended regulatory changes including improvements to the informed consent process.
A Scottish report stated they “remained concerned regarding the safety and efficacy of the transvaginal meshes”.
In Australia, the Therapeutic Goods Administration (TGA) formed the Urogynaecological Devices Working Group to advise on this issue. Due to concerns over the lack of definitive data, the group is reassessing clinical evidence for each transvaginal mesh product to ensure it complies with the TGA’s requirements for safety and performance. These evaluations are ongoing.
It is concerning also that many of the mesh products already evaluated were voluntarily withdrawn from use in 2011 to be replaced with newer, lightweight transvaginal permanent meshes. These have yet to be evaluated but remain in use.
What we found
Our research aimed to offer women and health professionals the evidence to make better informed choices about surgical treatment.
We found transvaginal mesh surgery had benefits. It reduced the risk that women would be aware of the vaginal bulge from 18% in those who had traditional repairs to 12% in those who had mesh repairs, one to three years following the surgery.
The rate of repeat operations for prolapse following transvaginal permanent mesh repair (1-3%) was also lower compared to traditional repairs (3%).
But some problems were reported with transvaginal mesh. The average rate for repeat operations for prolapse, urinary incontinence, or mesh exposure after mesh repair, was 11% compared with around 5% in women who had a traditional tissue repair.
Permanent mesh surgery was also associated with higher rates of bladder injury than traditional tissue repair and higher rates of urinary incontinence with activity after the surgery.
And, as already mentioned, one in 12 women experienced unpleasant symptoms from mesh complications.
Clinicians and women should be aware that the benefits of transvaginal mesh as compared to traditional repairs should be carefully weighed against the complications.
Gynaecologists should be wary of adopting innovations that have not been fully evaluated by clinical trials. Our patients deserve better studies and, in the absence of evidence, better advice.
Authors: The Conversation Contributor