A disease that affects one in 10 women of childbearing age, that forces young girls to take days off school, older women to abandon careers and condemns others to childlessness should not be near-invisible. And yet endometriosis is rarely discussed, and when it is, it is often obscured by myths suggesting that women themselves are in some way to blame. Many are ashamed to admit to suffering, and often doctors seem ill-prepared to diagnose and treat the disease. It is a secret plague; yet it could afflict as many as 176 million women around the world.

The disease is caused by tissue similar to the lining of the womb growing – and bleeding – in places it should not. As time goes on, it spreads. It can even fuse organs together. It can take a woman years to realise that there is something wrong with her and find out what it is. When a 15-year-old is doubled up with savage period pains and has to take time out of the classroom, there is a tendency for her family as well as her doctor to think she’s just unlucky, and it is nothing that a hot water bottle and paracetamol can’t fix. But it is not normal. And, as Hilary Mantel has written, the time lost can be impossible to redeem. By the time she found out she had endometriosis, she could no longer have children. Her personal loss will be familiar to thousands of others.

Endometriosis is hard to diagnose without invasive surgery, probably a laparoscopy, keyhole surgery that allows a gynaecologist to identify and if necessary remove damaging tissue, which primary care doctors are often reluctant to recommend. Most women are first prescribed a contraceptive pill, which can help. Far too many still tell of being sent away by a doctor who tells them it’s all in their head.

These women need to see a gynaecologist, but not just any gynaecologist. There are still some who think that open surgery to remove the womb and ovaries is the answer, and then are stumped when it becomes clear that the disease is in the bowel. Fortunately, a group of pioneering doctors at the British Society for Gynaecological Endoscopy have set up an accreditation centre for UK hospitals that have endometriosis specialists; more than 40 units are now accredited, but women are still faced with the old postcode lottery. In Wales, for example, there is just one such centre.

There are dedicated, pioneering doctors in many countries who can carry out the highly complex keyhole surgery needed to cut out all accessible tissue. But too often women do not get to see them. In the United States, health insurance schemes refer women to a nearby gynaecologist, not necessarily somebody specialised in endometriosis. In Australia, women may have to pay privately and travel hundreds of miles to reach a specialist.

So many women affected and so much to do. There are issues at every level. First, there is a social and cultural conundrum. Nobody wants to talk about periods. All around the world, women grow up in an environment where the appropriate response to pain is resignation. That needs addressing, starting in school. If girls and boys are taught about sex and their reproductive organs, they could also be told there that pain during menstruation and intercourse can be caused by this disease.

Second, with so many women affected, endometriosis should surely register higher on the index of suspicion of primary care doctors. That may need tackling in medical school.

Third, surgery should always be carried out in accredited specialist centres. It happens for heart disease and cancer. Endometriosis is not life-threatening, but it is certainly life-wrecking, and it should be treated no differently from such diseases. And it is essential that more money should go into research into both cause and effective treatment, so that women no longer find themselves facing premature menopause as the alternative to debilitating pain.