A health expert has provided insight into new numbers around surgeons' ability to use surgical mesh

Due to concerns about avoidable harm -- the Health Ministry's set up a credential process for highly-specialised urogynecological operations.

In the first round of assessments, 12 surgeons applied - but only half met the requirements.

Wellington Hospital's Clinical Lead for Gynaecology, Nick Bedford says the assessments were for procedures relating to the complications of mesh.

He says it's a very highly specialised area of surgery -- and agrees in a country the size of New Zealand, there should only be a handful of people doing those procedures.