Andrew Horne, a professor of gynaecology at Edinburgh University, said failure to develop a blood or urine test had halted progress in tackling the disorder, which affects one in ten women – roughly 1.5 million in the UK.
Endometriosis is a disorder where tissue that normally lines the inside of the uterus can grow anywhere in the body, most commonly the ovaries, fallopian tubes and the tissue lining the pelvis. It can cause considerable pain, and fertility problems.
Women can suffer a range of symptoms including severe and chronic period pain, pelvic pain, very heavy or irregular periods, fatigue and lack of energy.
The symptoms experienced will depend on where the endometriosis is growing, so vary from woman to woman.
The wait for a diagnosis in the UK is currently seven and a half years on average, meaning that women have no treatment for a lengthy period of time during which the disease may develop.
Research by Standard Life indicates women can lose an average of £40,000 in earnings while unable to work due to the disease. Currently only a laparoscopy – keyhole surgery on the abdomen and pelvis – carried out under general anaesthetic can confirm the presence of the condition.
Prof Horne said: “One of the main reasons that progress has not been made to shorten the time to diagnosis is the lack of a non-invasive biomarker that can be used to test for endometriosis – a blood or urine test, for example.
“This is because of the complexity of the disease and the fact that, most endometriosis research studies have been underfunded, on a small scale, and have involved poorly defined populations of women and samples.”
He added: “To deliver well-designed, large scale, collaborative research requires money. To see real progress, we need significant financial investment into endometriosis research and for that we need support from politicians and governments.
“If this investment is delivered, I believe that our campaign will herald the enticing promise of the steps towards … the identification of a simple test for endometriosis and, ultimately, a cure.”
Prof Horne is among those whose portraits have been taken by leading photographer Rankin as part of an exhibition which closes today at Stills Gallery in Edinburgh. The Beyond the Invisible exhibition features the stories of 15 women living with the challenges of the disease.