The symptoms of endometriosis

The symptoms of endometriosis are wide, often misleading, and easy to mistake for something else. They differ from one woman to the next, they overlap with other conditions, and they have a way of being explained away, sometimes for years. Knowing them in detail is one of the most useful things a woman can do, both to recognise the disease in herself and to be heard when she describes it.

This article sets out the symptoms one by one, from the most familiar to the least known. It is written to inform, and it does not replace a consultation with a physician.

Pain, in its many forms

Pain is the most common reason endometriosis comes to attention, and it rarely takes a single shape. Physicians give each form its own name, which is worth knowing, because a woman who can name what she feels is harder to dismiss.

Painful periods (dysmenorrhoea) are the most frequent symptom and usually the most intense. This goes far beyond ordinary period discomfort: pain severe enough to keep women home from school or work, that ordinary painkillers do not settle, and that often begins a day or two before bleeding starts.

Chronic pelvic pain is pain that no longer keeps to the menstrual calendar. It can be present on any day of the month, dull or sharp, and it is one of the signs that the disease has been at work for some time. The pain that does not ease when the period ends is often what finally raises suspicion.

Pain during sex (dyspareunia) is typically felt deep rather than at the surface, during or after intercourse. It is common, frequently unspoken, and a meaningful clue when present.

Painful bowel movements (dyschezia) and painful urination (dysuria) point to lesions near or on the bowel and bladder. They are often worse around the period, and can come with changes in bowel habit or, more rarely, blood in the stool or urine.

Pain at ovulation and lower back pain are common too, the first appearing around mid-cycle, the second often radiating from the pelvis and mistaken for an everyday backache.

The pain of endometriosis tends to be cyclic at first, tied to the period, then chronic, and often progressive, meaning it can intensify over the years if the disease goes unaddressed. Some women also develop a heightened sensitivity in which ordinarily painless sensations become painful, a sign that the nervous system itself has begun to take part in the pain.

When nerves are involved

In some women, deep lesions reach the nerves of the pelvis, most often the sciatic nerve, the sacral nerve roots, or the pudendal nerve. The pain then radiates beyond the pelvis, into the buttock, the back of the thigh, or down the leg, sometimes with numbness, tingling, or weakness, and it often flares with the period. When sciatic pain follows the cycle in this way, it is called catamenial sciatica. Because the nerve is affected inside the pelvis rather than in the back, a spinal scan can look normal, and the cause can go unrecognised for a time. This is a rare form, and the cyclic timing is usually the clue that points to it.

Symptoms far from the pelvis

Although endometriosis settles most often in the pelvis, it can appear in places that seem to have nothing to do with it. These forms are rare, and what links them is timing: symptoms that arrive and recede with the menstrual cycle.

On the diaphragm and in the chest, lesions can cause pain in the chest or the shoulder, often on the right side and felt up toward the shoulder blade, along with breathlessness. In rare cases they cause coughing of blood, or a small collapse of the lung, around the time of the period. This is known as thoracic endometriosis, and because it imitates more common chest complaints, its link to the cycle is easily overlooked.

At the navel or in a surgical scar, particularly after a caesarean, endometriosis can form a small lump that swells and becomes painful during menstruation, and that occasionally bleeds. A tender nodule at the belly button or along an old scar that changes with the cycle is characteristic of this form.

Beyond pain

Endometriosis is not only a disorder of pain, and some of its most overlooked symptoms involve no pain at all.

Heavy or irregular bleeding, including bleeding between periods, is common.

Digestive symptoms are frequent and frequently misattributed: bloating pronounced enough to change the shape of the abdomen, sometimes called endo belly, along with nausea and bouts of constipation or diarrhoea that come and go with the cycle. Because these resemble irritable bowel syndrome so closely, they are a common source of misdiagnosis.

Urinary symptoms can include needing to pass urine more often, urgency, discomfort, and cyclic pain when the bladder is involved.

A whole-body disease

Many of the symptoms already described have long puzzled women and clinicians, because they seem to have little to do with the pelvis. A growing body of research offers an explanation: endometriosis is increasingly understood as a systemic inflammatory disease rather than a local gynaecological one, a condition that involves the immune system throughout the body.

The lesions do not sit quietly. They release inflammatory signalling molecules, called cytokines, and these do not stay confined to the pelvis. They enter the bloodstream, where they can reach the brain and the body's regulation of energy, which helps account for a cluster of symptoms that are common in endometriosis and easily dismissed: a deep, persistent fatigue that rest does not lift, diffuse joint and muscle pain, difficulty with concentration and memory that many women describe as brain fog, and a heightened sensitivity of the immune system. It also helps explain something long observed but poorly understood, that removing the lesions surgically does not always bring the symptoms to an end.

For years, symptoms like these were treated as unrelated to endometriosis, or as having no clear cause at all, and they remain underemphasised even in many clinical guidelines, though they can be as disabling as the pelvic pain itself. The systemic view holds that they are real, and that they may be direct biological consequences of chronic inflammation rather than secondary effects of living with pain. For many women, this is the part of the picture that finally makes their own experience legible.

Difficulty conceiving

For some women, the first sign of endometriosis is difficulty becoming pregnant, with no pain at all. The link is well established: endometriosis is found in a substantial share of women evaluated for infertility, with estimates often placing it between a quarter and a half. The disease can affect fertility through adhesions, inflammation, and effects on the ovaries and egg quality. Many women with endometriosis do conceive, with and without help, but the association is strong enough that unexplained infertility is itself a reason to consider the disease.

The weight it carries

Living with pain that is chronic, often invisible, and frequently doubted takes a toll that is not only physical. Anxiety and low mood are more common among women with endometriosis than in the general population. The strain of living with chronic, doubted pain is the most evident reason, though recent work raises the possibility that the same systemic inflammation acts on the brain directly, giving mood a biological link to the disease as well. Either way, this is a real and recognised part of endometriosis, worth raising openly with a clinician rather than carrying alone.

What makes the symptoms so hard to read

Several things about these symptoms conspire to delay recognition.

The severity of the symptoms does not track the extent of the disease. A woman with small, superficial lesions can be in debilitating pain, while another with extensive disease feels little or nothing. Endometriosis can even be entirely silent, found only by chance. This disconnect is one of the deepest puzzles of the disease, and one of the reasons it cannot be judged by symptoms alone.

The symptoms also overlap with other conditions. Irritable bowel syndrome, painful bladder syndrome, fibromyalgia, and migraine all share ground with endometriosis and often coexist with it, which can send the search for an explanation in other directions.

And many of these symptoms begin early. More than half of women with endometriosis trace their first symptoms to adolescence, an age at which severe period pain is too often treated as something simply to be endured.

When symptoms are worth taking further

No single symptom confirms endometriosis, and most women with painful periods do not have it. But certain patterns deserve attention rather than patience: period pain that disrupts ordinary life or does not respond to usual painkillers, pelvic pain present outside menstruation, pain during sex, cyclic digestive or urinary symptoms, and difficulty conceiving. Symptoms that recur with the menstrual cycle, month after month, wherever in the body they appear, are a particularly clear signal.

If these are familiar, they are reason enough to ask for an evaluation, and to keep asking until the question is properly answered.

Geneviève is a diagnosis program for endometriosis and complex gynaecological conditions, built around a single belief: that every woman deserves a precise, thorough answer, delivered with care.

This article is for information and does not replace a consultation with a physician.