A medical expert says the benefits of surgical mesh in vaginal surgeries were never worth the risk.

Medsafe has restricted supply of the product for transvaginal surgeries, after hundreds of patients with the mesh were left in constant pain.

International Urogynaecological Association president Lynsey Hayward said the mesh was supposed to give extra support, but as she told Rachel Smalley, the mesh was simply too strong.

"If you can imagine you've broken your arm and you put your arm into a plaster cast, over months and years that muscle with wither away."

Hayward spoke to Newstalk ZB earlier and said that overall the technology is still useful.

She said there are other types of mesh that work well.

"The complication rates are low and they have been proven to be, particularly in terms of strength for urinary incontinence, the best treatment that we have to date when you compare all treatments."

She said the issue can be traced back to a Food and Drug Administration policy in the US.

The policy allowed for the mesh to be approved without rigorous testing, as it was seen as similar to other surgical meshes.

Hayward hopes that lessons are learnt from the use of surgical mesh.

"The biomechanics, so the understanding about what stresses and strains occur, weren't understood either. This has been a very big learning curve and I would hope it would not happen again."

LISTEN TO LYNSEY HAYWARD TALK WITH RACHEL SMALLEY ABOVE