Researchers have developed a non-surgical test that could be used to tell whether men with zero sperm counts might be able to father children via IVF.

The study, led by a team from Toronto's Mount Sinai Hospital identifies two proteins in semen that can be used as biological markers to predict the likelihood of finding sperm though surgical investigation. Currently, testicular biopsy is the only diagnostic method to determine the specific cause of the infertility.

Non-obstructive infertility refers to the failure of sperm to develop properly. In this case retrieving sperm for use in IVF is very difficult, and often impossible. But when the cause is obstruction in a man’s reproductive system, sperm retrieval is much easier.

Study leader Professor Keith Jarvi told The Canadian Press his team was 'trying to eliminate unnecessary surgery for the patient'.

He added: 'You can avoid biopsies in many of the men. And I think for a lot of the men, they just want to know what their options are earlier on'.

The pair of proteins - ECM1 and TEX101 – were selected from 2,000 candidate biomarkers. Their predictive value was tested first in 30 patients, then on an additional 119. The researchers were able to distinguish obstructive from non-obstructive infertility every time, although the test could not be considered 100 percent accurate.

Study lead author Dr Andrei Drabovich told The Canadian Press that the team was working to draw on samples from other clinics to confirm the findings.

Speaking to BBC News, Dr Allan Pacey, senior lecturer in andrology at the University of Sheffield and chair of the British Fertility Society, said the study was 'very encouraging indeed'.

'Having an accurate biochemical test which might help doctors advise men whether taking a piece of the testicle is worth doing or not, would be very useful', he said.

'It could help men make better decisions, avoid unnecessary surgical procedures and potentially help save money by not having to do surgical procedures that aren't needed'.

Work is now underway to adapt the test for use in fertility clinics. 'Optimistically, it would be a year away, pessimistically, two years - we're moving along really quickly', Dr Jarvi told the BBC.

Reproduced from BioNews with permission, a web- and email-based source of news, information and comment on assisted reproduction and human genetics, published by Progress Educational Trust.