Endometriosis

What it is

Endometriosis is a long-term condition where cells similar to those in the lining of the womb grow in other parts of the body, most often around the pelvis, ovaries and fallopian tubes. Each month this tissue can react to your cycle in the same way the womb lining does, which can cause inflammation, pain and scarring. It's common, affecting around 1 in 10 women and people assigned female at birth of reproductive age.

Common symptoms

Everyone's experience is different, but symptoms often include:

• pain in your lower tummy or back, often worse during your period
• period pain that stops you doing your normal activities
• pain during or after sex
• pain when peeing or pooing during your period
• feeling sick, constipation, diarrhoea, or blood in your pee during your period
• fatigue, and difficulty getting pregnant

Why diagnosis takes so long

Endometriosis symptoms vary a lot and overlap with other conditions, and pain around periods is still too often treated as normal. As a result, many people wait years for answers. In the UK, it takes an average of 9 years and 4 months to be diagnosed with endometriosis (Endometriosis UK, March 2026).

New Zealand: the average time to diagnosis is around 9.7 years (Ellis & Wood, ANZJOG, 2024).

How tracking helps

You can't diagnose endometriosis yourself, but a clear record of your symptoms over time can help you and your doctor. Logging when pain appears, how severe it is and what else is going on makes patterns visible, and a Doctor's Report gives you a simple summary to bring to appointments, so the conversation starts with evidence rather than memory.

Where to get support

• NHS: Endometriosis
• Endometriosis UK

If you think you might have endometriosis, speak to your GP.

Sister Health does not provide medical advice, diagnosis or treatment. Always consult a qualified healthcare professional. In an emergency, call 999 in the UK or 111 in New Zealand.