Endometriosis

Endometriosis affects an estimated 10% of women of reproductive age worldwide—approximately 190 million people—causing chronic pain, heavy bleeding, and often years of uncertainty before diagnosis. This condition occurs when tissue similar to the lining of the uterus grows in places where it doesn’t belong, leading to inflammation, scarring, and symptoms that can profoundly impact daily life.

Table of contents

• What is endometriosis?
• Where endometriosis develops
• Symptoms
• Causes and risk factors
• Diagnosis
• Treatment options
• Living with endometriosis

What is endometriosis?

Endometriosis is a chronic condition where tissue similar to the endometrium (the lining of the uterus) grows outside the uterus^[1][2]. This displaced tissue responds to the hormonal changes of your menstrual cycle just like the tissue inside your uterus does. Each month, it builds up, breaks down, and bleeds. However, unlike menstrual blood that leaves your body through the vagina, this blood has nowhere to go^[3]. As a result, it causes inflammation, irritation, and can lead to the formation of scar tissue that binds tissues together^[1].

This condition is common, affecting about 1 in 10 women worldwide during their reproductive years^[3][2]. Healthcare providers most often diagnose it in people in their 20s and 30s, though it can also affect teenagers and can persist even after menopause^[3][4]. The condition can also affect transgender men and non-binary individuals who menstruate^[2].

Where endometriosis develops

• Ovaries
• Fallopian tubes
• Space behind the uterus
• Uterine wall (myometrium)
• Peritoneum (lining of the pelvis)
• Uterosacral ligaments
• Bladder
• Bowel and rectum
• Intestines
• Vagina
• Diaphragm
• Lungs and chest (rarely)

Endometriosis most commonly occurs in the pelvis, affecting the ovaries, fallopian tubes, and the lining of the pelvic area^[1][2]. The ovaries are particularly susceptible, and when endometriosis affects them, it can form fluid-filled sacs called endometriomas, sometimes referred to as “chocolate cysts” because of their dark, thick contents^[1][5].

In some cases, endometriosis can affect organs beyond the reproductive system. It may involve the bladder, causing pain during urination, or the bowel, leading to painful bowel movements^[3][4]. Rarely, endometriosis is found in areas outside the pelvis entirely, such as in the chest, which can cause shortness of breath and coughing up blood^[2][4].

Symptoms

The symptoms of endometriosis vary widely from person to person. Some women experience debilitating pain that disrupts their daily activities, while others may have extensive endometriosis but feel little or no discomfort^[1][3]. Importantly, the severity of symptoms does not always correspond to the extent of the disease^[3].

The most common symptom is pelvic pain, which can be intense or mild^[3]. This pain often worsens just before and during menstrual periods due to inflammation caused by hormonal changes^[3][1]. Many women describe it as severe menstrual cramps that prevent them from carrying out normal activities^[4].

Other common symptoms include^[3][4][2]:

• Heavy menstrual bleeding or bleeding between periods
• Chronic pelvic pain that persists beyond the menstrual cycle
• Pain during or after sexual intercourse
• Pain when having a bowel movement or urinating
• Extreme tiredness (fatigue)
• Digestive problems such as diarrhea, constipation, bloating, or nausea
• Lower back pain during periods
• Difficulty getting pregnant (infertility)

Some women also experience low mood, anxiety, or depression, which can be linked to living with chronic pain and the emotional impact of the condition^[2][4]. It’s also possible to have endometriosis without any symptoms at all—some women only discover they have the condition when they have difficulty getting pregnant^[3].

Causes and risk factors

The exact cause of endometriosis remains unknown^[2][3]. Healthcare providers and researchers have developed several theories to explain why endometrial-like tissue grows outside the uterus, but no single explanation accounts for all cases.

The most widely accepted theory is Sampson’s theory, which suggests that during menstruation, some menstrual blood flows backward through the fallopian tubes into the pelvic cavity instead of leaving the body through the vagina—a phenomenon called retrograde menstruation^[5][3]. The viable cells in this blood can then implant and grow on pelvic structures. While retrograde menstruation is common in many women, not everyone develops endometriosis, suggesting that other factors are involved^[5].

Emerging research suggests that endometriosis may be associated with problems in the immune system^[2]. Women with endometriosis have higher rates of other immune-related conditions, such as lupus, multiple sclerosis, and inflammatory bowel disease^[2]. Hormone disorders, particularly those involving estrogen, may also play a role, as estrogen promotes the growth of endometrial tissue^[1].

Several risk factors can increase the likelihood of developing endometriosis^[3][1]:

• Family history—having a mother, sister, or grandmother with endometriosis
• Never having given birth
• Menstrual cycles that occur more frequently than every 28 days
• Heavy and prolonged menstrual periods lasting longer than seven days
• Higher levels of estrogen in the body
• Starting menstruation at an early age

Diagnosis

Diagnosing endometriosis can be challenging and often takes a long time. On average, it takes between 4 and 12 years from the first symptoms to receive a diagnosis^[2]. This delay occurs for several reasons: symptoms can vary widely and may overlap with other conditions, many women assume severe period pain is normal, and some healthcare providers may dismiss concerns or misdiagnose the condition^[2][4].

If you think you might have endometriosis, it’s important to see your doctor, especially if symptoms are affecting your everyday life, work, or relationships^[4]. Your doctor will start by asking detailed questions about your menstrual history, including the intensity of pain, heaviness of bleeding, and any other symptoms^[2][4]. They may also ask about your family history, since endometriosis tends to run in families.

During the appointment, your doctor may perform^[4]:

• A physical examination, including an internal pelvic exam to check your abdomen and pelvic area
• Blood tests

If your doctor suspects endometriosis, they may refer you to a specialist called a gynecologist for further testing. Additional tests can include^[4][2][8]:

• Ultrasound scan—This may be done on your abdomen or inside your vagina. Ultrasound is often the first imaging test used to look for signs of endometriosis
• MRI scan—This imaging test is preferred if deep infiltrating endometriosis is suspected
• Laparoscopy—This is a surgical procedure where a camera is passed through a small cut in your abdomen to look inside. It remains the definitive method for diagnosing endometriosis, as it allows doctors to see the endometrial tissue directly and take samples for examination

However, not all cases require surgery for diagnosis. Several gynecologic organizations now recommend starting treatment based on symptoms alone, without immediately performing surgery, especially if the clinical picture strongly suggests endometriosis^[8].

Treatment options

There is currently no cure for endometriosis^[2]. Treatment focuses on managing symptoms—particularly pain—and limiting the long-term impacts of the condition. The choice of treatment depends on the severity of symptoms, whether you want to become pregnant, and how well you tolerate different medications^[2][4].

Medications

Medicines are often the first treatment approach for endometriosis. They can help control pain and reduce the activity of the endometrial tissue^[4][8].

Pain relievers: Over-the-counter medications such as paracetamol and ibuprofen can help ease pain. These nonsteroidal anti-inflammatory drugs (NSAIDs) work best when taken a few days before your period starts, before pain becomes severe^[4].

Hormonal therapies: These medications work by changing the hormone levels in your body to suppress or stop your menstrual cycle, which reduces pain and prevents endometriosis from worsening^[1][4]. Common options include:

• Combined hormonal contraceptives—Birth control pills, vaginal rings, or patches that contain both estrogen and progestin. These are considered first-line treatment and are most effective when used continuously (skipping the hormone-free week)^[12]
• Progestin-only treatments—Such as the “mini-pill,” hormonal IUDs, or injections. These can help thin the uterine lining and reduce pain^[12]
• GnRH agonists—These medications create a temporary menopause-like state by dramatically lowering estrogen levels. They are effective but may cause side effects like hot flashes and bone loss. “Add-back therapy” with small amounts of hormones is often used to reduce these side effects^[10]
• GnRH antagonists—A newer option that works similarly to GnRH agonists but with fewer side effects^[10]

It’s important to note that hormonal therapies are not suitable if you’re trying to get pregnant^[4].

Surgery

If medications aren’t working, if you have severe endometriosis, or if the condition is affecting your ability to have children, surgery may be recommended^[4][8]. Surgical options include:

• Removing areas of endometriosis or ovarian cysts caused by the condition
• Removing the uterus (hysterectomy) or ovaries (oophorectomy)
• Removing parts of affected organs, such as the bladder or bowel, if endometriosis has spread there

Surgery can provide significant relief, but symptoms may return over time, and some women need additional surgeries^[4]. During a laparoscopy, doctors may be able to remove endometriosis tissue at the same time they confirm the diagnosis^[4].

Other supportive treatments

In addition to medical and surgical treatments, other approaches can help manage symptoms^[4]:

• Advice on managing chronic pain and extreme tiredness
• Referral to a fertility specialist if you’re having difficulty getting pregnant
• Mental health support if you’re experiencing low mood or anxiety

Living with endometriosis

Living with endometriosis can be challenging, but there are many strategies that can help you manage symptoms and improve your quality of life. Because endometriosis is a chronic condition, learning to cope with it over the long term is important.

Pain management at home

Simple approaches can provide relief from pain. Using heat therapy—such as a heating pad, hot water bottle, or warm bath—can help relax muscles and ease pelvic pain^[14]. Heat increases blood flow to the area and can reduce cramping.

Diet and lifestyle

While no specific diet can cure endometriosis, certain dietary choices may help reduce inflammation and support overall health. It’s important to ensure your diet meets all your nutritional needs, including energy, fats, protein, vitamins, and minerals^[17].

Research suggests that diets high in red meat and processed foods may worsen symptoms, while foods with anti-inflammatory properties—such as fruits, vegetables, whole grains, oily fish, olive oil, and nuts—may be beneficial^[14][17]. Omega-3 fatty acids found in foods like fatty fish, walnuts, and flaxseeds may help reduce inflammation^[14].

Limiting caffeine and alcohol may also help, as caffeine has been shown to increase estrogen availability, which can promote endometriosis activity^[17]. Staying well-hydrated by drinking at least 2 liters of water daily helps your body function properly^[17].

Exercise and physical activity

Regular exercise can help reduce pain, improve mood, and increase energy levels^[14]. When you exercise, your body produces less estrogen and releases natural pain-relieving chemicals called endorphins. Both high-intensity activities like running or cycling and low-intensity exercises like yoga or Pilates can be beneficial^[14][16]. Aim for about 30 minutes of exercise most days of the week, but listen to your body and don’t push yourself too hard if you’re in pain^[14].

Supplements

Some supplements may be helpful in managing endometriosis symptoms. Vitamin D is important for managing inflammation, and many people are deficient in it. Consider taking a vitamin D supplement, especially during winter months^[17]. Magnesium may help with muscle relaxation and pain management and can be taken as a supplement or absorbed through bathing in magnesium salts^[17].

Emotional and mental health support

The chronic pain and uncertainty associated with endometriosis can take a toll on mental health, leading to feelings of depression, anxiety, frustration, or anger^[14][15]. Seeking emotional support is essential. This can come from friends and family, support groups, or mental health professionals^[14][4]. Connecting with others who understand what you’re going through can be particularly helpful and can reduce feelings of isolation.

Managing work and daily activities

Endometriosis can significantly affect your ability to work and perform daily activities. It’s important to communicate with employers about your needs and explore flexible working arrangements if necessary. Don’t hesitate to take time off when symptoms are severe—prioritizing your health is not a sign of weakness.

Many women with endometriosis find themselves “faking it” to appear normal despite experiencing significant pain^[15]. While this may sometimes be necessary, it’s also important to advocate for yourself and seek the support and accommodations you need. Building a good relationship with experienced, supportive healthcare providers who take your concerns seriously can make a significant difference in managing the condition.