Scientists have created a tiny device which could help infertile couples conceive naturally.

Experts at the University of Southampton have developed an implant the size of a 5p piece that monitors oxygen, pH and temperature levels inside the womb.

It could help clinicians compare the range of levels found in women who have conceived naturally with patients from fertility and miscarriage clinics.

Around one in seven couples in the UK have difficulties getting pregnant and in a quarter of those cases doctors are unable to find the cause.

Professor Ying Cheong, a consultant in reproductive medicine at University Hospital Southampton NHS Foundation Trust, said: “Currently, fertility tests take time and some couples may not receive a diagnosis for their issues straight away and, in some cases, not at all, so we are constantly in need of new ways of establishing problems.

“By establishing a ‘normal’ range of levels which can be compared to those who experience difficulties conceiving, there is the potential to diagnose fertility issues sooner and inform the development of new treatments.”

The device is implanted in a similar way to a contraceptive coil and sends readings wirelessly to a data chip attached to a special set of underwear worn by the patient.

Prof Cheong said the technology could lead to “big changes” in fertility care worldwide.

“We want to get to the stage where we know what a healthy womb environment looks like and to make measuring levels inside the womb as simple as taking a blood pressure reading,” she said.

“If we can prove this device works successfully and is comfortable and safe, then we have the chance to make big changes to fertility care across the NHS and internationally and help to give many more women the best chance of conceiving.”

She is leading a world-first study into use of the technology involving 30 patients being carried out at Complete Fertility Centre Southampton.