PCOS to be renamed PMOS – what does that mean for women’s health?

A condition that affects 170 million women and girls worldwide has been given a new name to reduce the chances of missed diagnoses and inadequate treatment.

After more than a decade of global consultation, polycystic ovary syndrome (PCOS), a common condition that impacts how a woman’s ovaries work, will now be referred to as polyendocrine metabolic ovarian syndrome (PMOS).

The name change was published in the Lancet and announced at the European Congress of Endocrinology in Prague on Tuesday, after 14 years of collaboration between international societies and patient groups across six continents.

The renaming was spearheaded by the endocrinologist Prof Helena Teede, the director of Melbourne’s Monash Centre for Health Research and Implementation. For too long, experts including Teede say, the misleading nature of the term “polycystic” in PCOS contributed to delayed diagnosis and inadequate medical care.

Announcing the new name at the European Congress of Endocrinology in Prague on Tuesday, Teede said the term PCOS didn’t capture the “multi-system burden that people with this condition have suffered”, and that it “directs attention to only one organ”.

PMOS is hoped to better reflect the condition’s complex nature – which affects not only a females reproductive system but also the metabolism and the risk of diabetes and cardiovascular disease.

The NHS PCOS information page says that one of the three main features of the condition – polycystic ovaries – is when ‘your ovaries become enlarged and contain many fluid-filled sacs (follicles) that surround the eggs’, but that ‘despite the name, you do not actually have cysts if you have PCOS’.

The other two main features, it notes, are ‘irregular periods – which means your ovaries do not regularly release eggs’ and ‘excess androgen – high levels of “male” hormones in your body, which may cause physical signs such as excess facial or body hair’.

While in healthy women, multiple follicles typically start to develop within an ovary each month, eventually leading to one reaching maturity and releasing an egg, in women with PCOS/PMOS, these sacs often can’t release an egg due to follicles not fully maturing, meaning ovulation doesn’t occur – making becoming pregnant difficult for some women.

To be diagnosed with PCOS/PMOS, women must have two of the three criteria listed above (irregular periods, excess androgen, polycystic ovaries), meaning you can have the condition without having polycystic ovaries – which was a big reason for the name change.

Professo Teede, has seen the old name’s impact first-hand, saying, “What we now know is that there is actually no increase in abnormal cysts on the ovary, and the diverse features of the condition were often unappreciated.”

“It was heart-breaking to see the delayed diagnosis, limited awareness and inadequate care afforded to those affected by this neglected condition.”

What is PMOS?

The three main features of PMOS are: irregular periods, excess androgen, and polycystic ovaries. Signs and symptoms usually become apparent during the late teens or early 20s.

They can include: irregular periods or no periods at all, difficulty getting pregnant as a result of irregular ovulation or no ovulation, excessive hair growth, weight gain, thinning hair and hair loss from the head, and oily skin or acne.

PMOS is also associated with a greater risk of developing health problems in later life, such as type 2 diabetes and high cholesterol levels.

“At different stages of your life you present in different ways,” says Prof Colin Duncan of the MRC Centre for Reproductive Health at the University of Edinburgh in Scotland.

The original name derived from a common feature of the condition – polycystic ovaries. But the moniker is misleading. “It implies there are cysts in the ovaries,” Duncan says. But that’s not the case.

He says the erroneous name probably arose when researchers first looked at the ovaries of people with the condition and saw multiple small fluid-filled sacs.

These sacs are not cysts, they are follicles – structures that contain an egg.

In healthy women, multiple follicles start to develop within an ovary each month, a process that eventually leads to one reaching maturity and releasing an egg, while the others wither away.

In women with PMOS the development of some follicles becomes paused, and often a follicle does not mature to release an egg. 

What causes the condition?

The exact cause is unknown, but PMOS often runs in families, and it is related to abnormal hormone levels in the body, including high insulin levels.

The development of polycystic ovaries is associated with an overproduction of androgens by the ovaries.

These male sex hormones are produced in all women but people with PMOS often have an excess.

This overproduction is usually caused by an imbalance between two other hormones: follicle-stimulating hormone and luteinising hormone. Research is ongoing into why exactly that hormone imbalance occurs.

Many women with PMOS are resistant to the action of insulin and produce higher levels of insulin to counter this, contributing to the increased production and activity of hormones such as testosterone.

How is PCOS/PMOS diagnosed?

The condition is now diagnosed based on what is called the Rotterdam Consensus. In this framework, women must have two of the following three symptoms: biochemical or clinical manifestations of high levels of androgens – for example excess facial or body hair, or acne – irregular periods, and polycystic ovaries.

“It means you can have polycystic ovary syndrome without polycystic ovaries or you can have polycystic ovary syndrome without an irregular period,” Duncan says.

How can PMOS be treated?

There’s no cure for PMOS, but symptoms can be treated.

If you have it and you’re overweight, losing weight and eating a healthy, balanced diet can help with some symptoms.

There are also medicines available to treat individual symptoms, including excessive hair growth, irregular periods and fertility problems.

A simple surgical procedure called laparoscopic ovarian drilling may be recommended if fertility medicines are not effective.