Discussion of the Use of Biological Mesh for Pelvic Organ Prolapse Repair

An article in Current Urology Reports Journal published in June of 2012 detailed the use of biological grafts in the repair of pelvic organ prolapse. Specific information is presented in this article regarding the complications associated with the different prolapse compartments (posterior, middle and anterior). When the pelvic floor weakens—generally due to childbirth, surgery, menopause or aging—organs can drop from their normal position causing significant discomfort, pain and a variety of other symptoms. There may also be a genetic predisposition which contributes to the development of pelvic organ prolapse. The authors state that by the age of 80, at least 11% of all women will require POP surgery.

Unfortunately, there is also a 30% chance of recurrence which will require subsequent surgical procedures. There are other patient characteristics which can increase the risk of pelvic organ prolapse as well as surgical failure including obesity, the number of children, a history of smoking, constipation or a chronic cough and the overall state of the immune system. To improve the overall results of POP surgery both biologic and synthetic meshes are used, however synthetic meshes—while improving anatomic results—can bring complications such as mesh extrusion or erosion. Biological grafts can offer similarity to recipient tissue, decreasing the recurrence rate. 

Biologic grafts are either harvested from the patient’s own body from the vaginal lining, the rectum or the thighs, and while there is no risk of rejection or transmission of disease, operating times are extended and there can be complications at the site of the graft. Allografts are grafts which are extracted from cadaver tissue, and while an overall good choice there is some risk of disease transmission. Xenografts come primarily from cows and pigs. With both allografts and xenografts, disease screening is performed and the techniques for harvesting are fairly standard. The processing techniques can vary, however, with no clear consensus regarding the best method.

Anterior compartment prolapse tends to be the most common form of pelvic organ prolapse. Anterior prolapse occurs when the bladder and/or urethra are protruding; the use of biological tissue in the repair of this type of prolapse has shown inconclusive results. Middle compartment prolapse can involve the uterus, bowel, rectum, bladder or vaginal vault. Comparing biologic grafts to synthetic grafts in the transvaginal and abdominal repair of middle compartment prolapse has shown biologic grafts to be inferior to synthetic. Posterior compartment prolapse involves the herniation of the anterior rectal into the vagina leading to sexual dysfunction and chronic constipation. While traditional repair of posterior prolapse has shown high rates of success, painful sexual intercourse can be a typical side effect.

Regarding biological grafts in pelvic organ prolapse repairs, the most common complications included graft erosions which were less serious than the synthetic mesh erosions. The FDA issued an updated warning in 2011 regarding the use of transvaginal surgical mesh stating there was insufficient evidence to show any benefits of mesh over more traditional methods and that mesh complications were “not rare.” Better patient monitoring following surgery is recommended by the FDA as well as alterations in the pre-market application approval process.