Are PMOS and endometriosis sisters?

The label of polyendocrine metabolic ovarian syndrome, PMOS (previously known as PCOS) or endometriosis can have physical and emotional consequences for women. It is important for both male and females to gain a better understanding of such conditions, the symptoms and the challenges they pose. Such knowledge can act as physical and emotional support in times of need. It creates a safe space where the person with PMOS is comfortable discussing their experiences, feelings and concerns knowing they are being heard and supported by the right people.

With research fast developing there is a plethora of information out there, so WHAT do you believe in and WHAT do you ignore and WHOM do you believe and WHOM do you ignore? Endometriosis and PMOS both affect females and can have similar symptoms. However, the causes and some key symptoms are different. 

Endometriosis is a painful disorder in which tissue that normally lines the inside of your uterus grows outside the uterus. (Read more on Endometriosis breakthrough). PMOS is an endocrine system disorder where small fluid-filled sacs develop in the ovaries. You can have endometriosis and PMOS at the same time. A 2015 study found that women with PMOS had a higher risk for a diagnosis of endometriosis. Another 2014 study determined that there is a strong link between endometriosis and PMOS with pelvic pain and trouble getting pregnant. 

What is a normal menstrual cycle?

Let’s polish up the basics! The brain, ovaries and uterus work together to prepare the body

per month for pregnancy. Follicle-stimulating Hormone (FSH) and Luteinising Hormone (LH) are made by the pituitary gland and progesterone and oestrogen are made in the ovaries.

Many females with PMOS do not ovulate regularly and it may take these females longer to

become pregnant. Irregular periods results in months where ovulation does not occur.

Where the ovaries do not produce progesterone the lining of the uterus becomes thicker but shedding is very irregular which can lead to heavy and prolonged bleeding.

PMOS affects 1 in 10 women in the UK. Women with PMOS experience irregular menstrual

cycles, acne, excess hair growth, infertility, pregnancy complications and cardiovascular

disease. PMOS can be associated with weight gain and obesity in approximately one-half of females. Females with PMOS can also be at increased risk of other problems that can

impact quality of life. These include depression and anxiety, sexual dysfunction and eating disorders. Although PMOS is not ‘completely’ reversible there are many ways you can minimise the symptoms. Most females can lead a normal life and are able to conceive

without significant complications.

A pelvic examination is requested by your GP to assess the ovaries for a diagnosis to be

made. Imaging tests for examining the ovaries are pelvic and intravaginal ultrasonography,

however, the latter may be extremely uncomfortable if sexually inactive.

Note: As of Oct 2025, NICE has announced it will adapt the International PMOS Guideline for the UK. Please be aware this article acts to capture your attention, encouraging you to delve further into the subject and continue your self-education on this topic and by no means is everything about PMOS. It is essential to consult with a healthcare professional if you suspect you may have symptoms of either PMOS or endometriosis. Proper diagnosis and management can help address specific concerns and improve overall reproductive health.

Written by Khushleen Kaur

Related articles: Endometriosis breakthrough / Underreporting in endometriosis / Gynaecology

REFERENCES

R. Hart and D. A. Doherty, Fertility Specialists of Western Australia (R.H.), Bethesda Hospital, 6008.

K. J. Holoch, R. F. Savaris, D. A. Forstein, P. B. Miller, H. Lee Higdon, C. E. Likes and B. A. Lessey, https://doi.org/10.5301/je.5000181, 2014, 6, 79–83.

R. J. Norman, D. Dewailly, R. S. Legro and T. E. Hickey, The Lancet, 2007, 370, 685–697.