Endometriosis – the symptoms, treatment and how it affects your fertility

19th August, 2022 • 18 min read

Periods and pain are common issues for lots of women every month. But if your period pain is so intense it stops you getting on with everyday life, you could be among the 1 in 10 women with endometriosis. This is a condition that means tissue like the lining of your womb grows in other parts of your body. That tissue bleeds every month, causing pain and other symptoms, sometimes along with fertility issues.

Severe period pain is a classic endometriosis symptom - it can be so bad it affects everything from your sleep to your work and social life. You may also have other symptoms that come with your period, like bleeding so heavy it soaks through protection and onto your clothes. Endometriosis is related to having periods but you may also have symptoms at other times of the month, including pelvic pain and pain during sex. Endometriosis can affect your mood, too, leaving you exhausted and low. And if you want to have a baby at some point, you may be really worried about how it might affect your fertility.

On top of all that, getting a diagnosis can take a long time, partly because it can be difficult to work out what’s normal, and hard to know how to explain endometriosis pain.

“Periods shouldn’t be so painful they make your life miserable,” says

Dr Ann Nainan
, doctor and Healthily expert. “Go and see your doctor if you think you may have endometriosis. They’ll be able to make a diagnosis if you have it - and offer treatment options, including surgery if you need it.”

Read on to find out all about endometriosis - and what you and your doctors can do to manage pain, other symptoms and any fertility issues.

What is endometriosis?

When you have endometriosis, tissue that’s like your womb lining grows in other parts of your body. This abnormal tissue swells and bleeds each month, just like the lining of your womb when you have your period. But unlike your womb lining, it can’t come out through your vagina. Instead, the abnormal tissue builds up where it is, causing inflammation and scar tissue (known as adhesions) that lead to long-term pain. There’s no cure and no known way to prevent endometriosis (which gets its name from the endometrium, the proper word for your womb lining). But there are treatments and surgery options that can really help.

Which parts of your body does endometriosis affect?

The most common areas where endometrial tissue builds up are:

  • your ovaries
  • your fallopian tubes
  • the ligaments that support your womb (uterosacral ligaments)
  • the space between your womb and your bladder
  • the space between your womb and rectum (back passage)
  • the outer surface of your womb
  • the lining of your pelvic cavity

Sometimes endometrial tissue also finds its way into your:

  • intestines
  • rectum
  • bladder
  • vagina
  • cervix (neck of the womb)
  • vulva (outer lips of your vagina)
  • lungs and liver

And if you’ve ever had surgery on your tummy - like a

Caesarean section
when you’ve had a baby - endometrial tissue can grow there too.

What are the signs and symptoms of endometriosis?

Intensely painful periods are the main sign. But up to 25% of women with endometriosis don't have any pain at all. They only find out they have endometriosis when they have problems getting pregnant, or find out by accident when having investigations for something else. And the level of pain you have doesn’t always reflect how severe the condition is. For instance, you may have intense pain even if you only have small areas of abnormal tissue. On the other hand, you may have quite widespread endometriosis without having severe pain.

Common signs of endometriosis include:

  • painful or
    heavy periods
  • pain in your tummy, pelvis, lower back or legs
  • pain during and after sex
  • bleeding between periods
  • fertility problems
  • fatigue, bloating, nausea, diarrhoea, constipation, usually around your period
  • depression or anxiety

Less common signs may suggest more severe endometriosis, which could have grown outside your pelvis. These signs can include:

  • bleeding from your bum
  • blood in your pee caused by abnormal tissue in your bladder
  • leg pain or
    , which can be a sign of abnormal tissues in your nerves
  • shortness of breath, if endometriosis is in your lungs

What does endometriosis pain feel like when you have your period?

  • it can feel like really severe cramping or dragging period pain in your tummy and/or lower back
  • but it can also feel different to period pain, with some women describing it as feeling like being stabbed with a knife or hot poker, or having a feeling of pressure, like a balloon pushing on everything
  • the pain may also affect your legs and the rest of your body
  • and it can cause other reactions, such as

What does endometriosis pain feel like when you’re not having a period?

  • it may happen during sex - women often describe this as pain that’s deep inside them
  • you may feel pain when you poo or pee
  • pain often starts a few days before your period

Who is more likely to get endometriosis?

Endometriosis usually starts a few years after you have your first period. It can get better during pregnancy, and it often stops after menopause. A few different things raise your risk, including:

  • having a close relative (mother, aunt or sister) with endometriosis
  • starting your periods early
  • going through menopause late
  • giving birth later in life
  • never giving birth
  • having short cycles (less than 27 days)
  • being slim - some research has linked this with a higher risk of endometriosis, especially in your teens. Scientists are still trying to understand the connection
  • any conditions that stop blood flowing out of your body when you have your period
  • reproductive tract disorders
  • having an autoimmune disease, such as rheumatoid arthritis or lupus, although more research is needed to find out why

What causes endometriosis?

Scientists don’t understand exactly what causes it. But there are a few theories - and endometriosis may be caused by a combination of things. Here’s what scientists think at the moment.

It could be caused by retrograde menstruation

normally, tissue from your womb lining comes out through your vagina when you have a period
retrograde menstruation means it flows back into your pelvis instead
scientists think this leaves bits of womb lining stuck on organs in your pelvis, which then start growing
but most women have some degree of retrograde menstruation and only some get endometriosis, so there’s still a lot that isn’t known

It may spread through your bloodstream or lymphatic system

  • scientists think womb lining tissue might be able to spread to other parts of your body in this way
  • it could explain why endometriosis can affect parts of your body far away from your womb, such as your lungs
  • but more research is needed

Cell changes

  • it may sound strange but sometimes, hormones like oestrogen can change cells in your tummy and pelvis into cells like the ones found in your womb lining
  • these cells then grow where they are
  • this could be another reason why patches of abnormal tissue are found far away from your womb, and might also explain why women can get endometriosis even after they’ve had a hysterectomy (surgery to remove the womb)

Things in the environment

  • dioxin is a toxin that’s been linked with endometriosis - it’s found in a few different things, including foods like meat and fish
  • but it hasn’t yet been proven that high levels of dioxin definitely cause endometriosis

Immune system problems

your immune system may not be able to recognise and destroy womb-like tissue growing in other places
women with endometriosis often have lowered immunity to other things, but scientists aren’t sure whether that’s a cause or a result of endometriosis

Genetic factors

although endometriosis is known to run in families, at the moment scientists don’t know whether there’s a specific gene that gets passed on and causes the condition

Self-care and natural treatments for endometriosis

If you know you have endometriosis or you’re waiting to be diagnosed, there are some things you can try to help with symptoms.

When you’re in pain

These may all help ease pain when you have it:

  • simple painkillers like
    - talk to your pharmacist about what’s best for you
  • heat treatment - a hot water bottle, heated wheat bag or warm bath can be really soothing
  • a TENS machine
    (from pharmacies) is an alternative to painkillers. It’s a device that sends little electric shocks through sticky pads you put on your skin, which feels like tingling. It may help reduce pain signals and may also raise levels of your body’s natural painkilling substances
  • relaxation - get comfortable and try to stay away from stress as much as possible

To help prevent symptoms

Try these things regularly to help prevent the worst of your symptoms:

  • “Being active might be the last thing you feel like as endometriosis can leave you so exhausted, but exercise can help build your core strength over time, and ease pain,” says Dr Ann Nainan. “It can also help manage stress. You don't need to do anything too challenging. Try some regular activity that you enjoy, like yoga, pilates or brisk walking.”
  • a physiotherapist can put together some exercises and relaxation techniques that may help by strengthening your pelvic floor, easing pain and managing stress
  • consider
    : more studies are needed but some research has found it may help with pain

Endometriosis and what helps me

Our health stories are designed to give women's voices more space and time to really share their experiences and tips with you. If you don't have time to watch the whole of Liz's video right now, you can:

  • just listen to the audio while you go about your day
  • bookmark this page to come back to when you've got a few minutes

Get support

Endometriosis can be isolating and frustrating, so having support from people can make a real difference:

  • friends, family and partners can all offer emotional and practical support, like taking on chores you can’t manage when you’re in pain
  • it can also be really helpful to talk to people who understand how it feels to have endometriosis
  • Endometriosis UK has a free
    staffed by trained volunteers with experience of endometriosis. It also runs an online support group, where you can connect with other women with endometriosis
  • The Endometriosis Foundation
    of America connects and supports women with endometriosis

When to see a doctor - diagnosis, treatment and surgery options

Endometriosis can sometimes get better on its own but not always - and it may get worse without treatment. On top of the pain, you may be feeling isolated, anxious or depressed, so getting diagnosed and treated can help you have a better quality of life. See your doctor if:

  • you’ve been getting intense period pain that isn’t eased by painkillers and stops you doing things you normally do
  • you’ve been struggling to get pregnant - around 25-50% of women with fertility problems have endometriosis

How is endometriosis diagnosed?

The symptoms of endometriosis are similar to the ones caused by

period pain
pelvic inflammatory disease (PID)
ovarian cysts
. This may be one reason it can take a while to get a diagnosis. Studies have found that on average, it can take at least six years to be diagnosed with endometriosis, although for some women it may take even longer.

Before you see your doctor

  • getting diagnosed with endometriosis isn’t straightforward so it can be helpful to keep a detailed diary of your symptoms. That way, your doctor gets a clearer picture of your pain and mood during the month. Endometriosis UK has a
    pain and symptoms diary
    template to help you do this - or use our
    Smart Symptom Checker
  • write down any questions you want to ask, such as what might be causing your symptoms and whether they’ll want to refer you for tests

In your appointment

  • your doctor will ask you questions - be honest about the level of pain you have and tell your doctor everything you’ve tried before to help
  • they’ll feel your tummy and do an internal pelvic examination to check for tenderness, inflammation and lumps. “Try not to worry about having this done - your doctor’s trained to do it and it shouldn’t take very long,” says
    Dr Adiele Hoffman
    , doctor and Healthily expert. “If it’s painful, you can ask them to stop at any time.”
  • if the doctor says something you don’t understand, ask them to explain it again - it’s important you’re clear about it

After your appointment

  • if you have more questions or concerns, you could book another appointment to talk things through
  • if you’re not happy with what the doctor says, ask to see another doctor or ask for a referral to a specialist

Your doctor should refer you to a gynaecologist if you have:

  • symptoms of endometriosis that are severe, don’t go away or keep coming back
  • you have signs of endometriosis in your pelvis
  • they think your symptoms might suggest endometriosis in your bladder, bowel or ureter (the tube your pee comes through)

Tests for endometriosis

When you see a gynaecologist, the main tests you may be referred for are:

  • ultrasound
    : this uses soundwaves to take pictures inside your body. It’s normally done with a probe inside your vagina. In some countries, you might also have sterile saline solution is injected into your womb to show growths and scarring
  • laparoscopy
    : you have this under anaesthetic but it’s a routine procedure that takes 30 minutes to 1 hour, and you can go home afterwards. A surgeon makes a very small cut in your tummy and puts in a thin tube with a light and camera on the end, which sends pictures from inside your pelvis to a TV monitor the doctors can see. Laparoscopy is the only way doctors can say for sure whether you have endometriosis

Stages of endometriosis

When you have a laparoscopy, doctors look at how much abnormal tissue there is, how big it is and where it is. Based on what they see, they may put your endometriosis into different stages. The stages don’t necessarily reflect how bad your symptoms are but can be useful for doctors to see how endometriosis may affect your fertility (if that matters for you) - the more severe it is, the more likely you are to have problems.

  • stage 1 (minimal): you have a few small bits of abnormal tissue growing and no scarring
  • stage 2 (mild): you have more areas of endometriosis but no scarring
  • stage 3 (moderate): there are more areas of endometriosis and it’s deeper. There may be pockets of fluid, called endometriomas or chocolate cysts, on your ovaries, and may have some scar tissue around your fallopian tubes or ovaries
  • stage 4 (severe): you have lots of abnormal tissue and may have big cysts on your ovaries, plus scar tissue between your uterus and rectum and around your ovaries or fallopian tubes
  • Doctors might also put endometriosis into these 3 different types to help them decide how to treat it:
  • peritoneal or superficial endometriosis is on the surface of your pelvic cavity and organs
  • deep endometriosis is below the surface - it’s spread into organs near your womb, like your bladder or bowel
  • endometriomas - sometimes called chocolate cysts - on your ovaries

Endometriosis treatment

If you only have mild symptoms that haven’t affected your fertility, you may not need treatment. Your doctor will decide on the best treatment for you based on a few different things, including:

  • your age
  • what your main symptoms are - such as pain or difficulty getting pregnant
  • whether you want to get pregnant (some treatments may stop you conceiving)
  • how you feel about surgery
  • whether you’ve tried any treatments before

How is endometriosis treated?


  • painkillers - apart from what you can get from the pharmacy, your doctor may prescribe
    NSAIDs (nonsteroidal anti-inflammatory drugs)
    such as ibuprofen and mefenamic acid. These normally work best if you take them a day or two before your period or before pain starts
  • hormone treatments work by limiting the release of the oestrogen that triggers endometriosis to grow in your body. These may include the
    contraceptive pill
    , which contains oestrogen and progesterone, and other treatments containing progestogens (the synthetic form of progesterone) such as the
    Mirena intrauterine system (IUS)
    , the contraceptive implant or injection, or progestogen pills. Progestogen treatments help ease pain and limit the growth of endometriosis. You may stop ovulating and having periods while you’re using them
  • GnRH analogues stop your body making oestrogen, creating a temporary menopause and starving the endometriosis of the hormone that feeds it. Usually, you’ll take a course for 3 to 6 months. You might need to take HRT alongside it to prevent side effects of an early menopause (you can expect your periods to come back a few weeks after you stop taking these)


Another option is surgery to cut away patches of endometriosis, leaving healthy tissue behind. It can be very effective. Not everyone needs surgery but it may be recommended if:

  • you want to get pregnant (the usual hormonal treatments stop you conceiving)
  • endometriosis has spread outside your womb and is in your bladder, bowel or ovaries
  • your endometriosis is severe
  • it’s not improving with other treatments

Patches of endometriosis are usually removed with one of these types of surgery:

  • ablation: a surgeon uses heat and electricity to burn away abnormal tissue. This is carried out under anaesthetic during a laparoscopy, and may even be done during a laparoscopy for diagnosis. It’s often used when the patches are near the surface
  • excision: the surgeon carefully cuts out areas of abnormal tissue, and this can be done with endometriomas and deeper areas of endometriosis as well as the patches closer to the surface. Excision is carried out by laparoscopy but the surgeon may need to make a wider cut along your bikini line. Although it’s a bit more invasive than ablation, it’s more likely to remove all the areas of abnormal tissue

Some women may be offered a

if other treatments haven’t helped. But this is a serious operation and doesn’t necessarily cure endometriosis if it’s spread outside your womb.

Your gynaecologist will talk through the pros and cons of types of surgery that may be suitable for you.

Endometriosis and infertility

Lots of women with endometriosis worry about getting pregnant. Some only find out they have the condition when they start trying to conceive. And even if you don’t know yet whether you’ll want to have children in the future, you may be really concerned that having endometriosis will take away your choices.

The condition can make it more difficult to get pregnant but the reassuring news is that around 7 in 10 women with mild to moderate endometriosis conceive naturally. Many women with more severe endometriosis can also get pregnant without fertility treatment.

How does endometroisis affect your fertility?

  • endometriosis can cause adhesions in or near your ovaries. These can block eggs travelling down your fallopian tubes
  • endometriomas in your ovaries can affect your fertility in various ways, including reducing the number of eggs you have and making eggs less likely to mature

How can treatment help fertility?

surgery to take away abnormal tissue and cysts can sometimes give you a better chance of getting pregnant. But the endometriosis may grow back and there’s a risk surgery itself may affect your fertility - your gynaecologist will be able to tell you about the pros and cons
you may be able to have fertility treatment (IVF) - it doesn’t guarantee you’ll conceive but it may improve your chances.

Doctor’s tip

“If you have endometriosis and want to have children, it’s best to think about trying for a baby earlier, if you’re in a position to do that,” says Dr Adiele Hoffman. “Age plays a big role in fertility, and if you end up having fertility treatment, it’s more likely to be successful if you’re younger.”

Find out more about

endometriosis and your fertility

Important: Our website provides useful information but is not a substitute for medical advice. You should always seek the advice of your doctor when making decisions about your health.