Severe period pain, endometriosis or PCOS – how can you tell the difference?

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Wondering whether your heavy periods or extreme period pain could be the sign of an underlying issue? Here’s what you need to know about two common, but often misunderstood, conditions

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Endometriosis and polycystic ovary syndrome (PCOS) are two conditions that affect millions of people around the world. PCOS affects around 8% to 13% of women and people with uteruses globally, and endometriosis affects around 10%. While they both can cause irregular bleeding and problems getting pregnant, there are some key symptom differences to be aware of.

Here, Dr Elisabeth Rosen, a medical doctor at Livi who specialises in gynaecology and obstetrics, gives her advice on how to tell if severe period pain and other symptoms are caused by PCOS or endometriosis, and when to talk to a doctor.

What is PCOS and what are the key symptoms?

‘PCOS is a complex disorder that causes elevated levels of sex hormones,’ says Dr Rosen. ‘Polycystic ovaries contain fluid-filled cysts known as follicles, in which eggs develop but usually never mature enough to ovulate. This affects the menstrual cycle, leading to irregular bleeding and problems ovulating.

‘In the long term, living with PCOS can lead to a higher risk of type 2 diabetes, cardiovascular diseases and uterine cancer.’

The most common PCOS symptoms include:

  • Irregular periods, long gaps between periods, or no periods
  • Excessive hair growth on the face, chest and abdomen
  • Weight gain
  • Acne

What is endometriosis and what are the key symptoms?

Endometriosis is an inflammatory condition in which cells similar to the ones in the lining of the womb are found elsewhere in the body, explains Dr Rosen. When these start to grow, they cause local inflammation and scarring. Endometriosis is most commonly found in the pelvis, but can be found in other parts of the body.

Not everyone who has endometriosis gets symptoms, and they can vary over time and between different people.

The most common endometriosis symptoms include:

  • Severe period pain
  • Heavy or irregular periods
  • Pelvic or lower back pain, outside of menstruation
  • Urinary tract problems, like blood in the urine or pain when emptying your bladder
  • Pain during sex
  • Pain while pooing
  • Fatigue and lack of energy

What’s the link between endometriosis, PCOS and infertility?

Both endometriosis and PCOS are linked to an increased risk of infertility. ‘As PCOS is a condition that causes problems with the release of eggs from the ovaries, it can make getting pregnant more difficult,’ says Dr Rosen.

More research is needed to determine why endometriosis affects fertility, but this may be caused by inflammation, scarring or deformation in the pelvic area. People who have minimal or mild endometriosis usually have a better chance of becoming pregnant than those with more severe cases.

How is PCOS diagnosed?

There’s no single definitive test to diagnose PCOS, which can make it harder to identify. A doctor will ask questions about your symptoms and experiences, explains Dr Rosen. They will refer you for a blood test to test your hormone levels and do an ultrasound to check for signs that your ovaries are polycystic.

How is endometriosis diagnosed?

Endometriosis can take 6 to 7 years on average to diagnose. Like PCOS, it’s usually a multi-stage process. Dr Rosen advises that a doctor will first ask about your symptoms, before referring you for further testing such as an ultrasound or laparoscopy – a form of keyhole surgery – to check for the presence of endometriosis lesions.

Can you have both PCOS and endometriosis at the same time?

There are people who have been diagnosed with both conditions, but Dr Rosen explains that while it’s possible, it’s not very common.

When should I see a doctor about severe period pain?

Severe period pain is more closely linked to endometriosis than PCOS. ‘If you can manage the pain with paracetamol or ibuprofen a couple of days per month and it decreases over a couple of years (after your periods have just begun), there’s usually nothing to worry about.’

Dr Rosen emphasises that if you’re concerned, it’s better to speak to a doctor, especially if your menstrual pain affects your ability to go to work or school.

How can I prepare to see a doctor about severe period pain – and increase my chance of a faster diagnosis?

Dr Rosen advises keeping track of your symptoms and menstrual cycle to help you spot patterns. You can use a cycle tracker app or a physical diary.

According to Dr Rosen, the more information you can give, the better. ‘Write any symptoms down that you feel may be associated with either your irregular bleeding (for suspected PCOS) or your severe period pain (for suspected endometriosis), including how long they last and when they occur,’ she says.

This also applies to painkillers. ‘Rather than just saying: “I take paracetamol,” it’s good to know how much, how often and for how many days,’ adds Dr Rosen.

What can I do if I feel my pain isn’t being taken seriously?

Unfortunately, many women encounter difficulties getting diagnosed with endometriosis and PCOS, but being aware of this can help.

If you don’t get a diagnosis immediately, you should keep pushing for answers, says Dr Rosen. ‘Even if it isn’t endometriosis or PCOS, a doctor will be able to carry out the necessary investigations to understand what’s causing your pain, irregular bleeding or other related symptoms.’

If you’re ever concerned about your period or period-related symptoms, book a meeting to discuss it with a doctor.

This article has been medically approved by Dr Elisabeth Rosen, a medical doctor at Livi who specialises in gynaecology and obstetrics.

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