How is endometriosis detected and diagnosed?

Published: 1 March 2023|Last updated: 6 March 2023|About Assisted Reproduction.|

In this post, we will explain how endometriosis is detected, as well as whether it can be treated, what causes may be behind its presence, its associated symptoms and to what extent endometriosis can be a cause of infertility. In addition, if you have already been diagnosed with endometriosis and are trying to get pregnant, we will tell you what options are available and which ones you will find at Eugin, the specialists in assisted reproduction and fertility.

Endometriosis is a condition in which tissue that lines the inside of the uterus (endometrial tissue) develops outside the uterus (ectopic). It affects approximately 10% (190 million) women and girls of reproductive age1 worldwide, regardless of ethnicity or social group.

Endometriosis most commonly affects the ovaries, fallopian tubes and the tissue lining the pelvis. When endometriosis affects the ovaries, cysts called endometriomas may form. In some cases, this tissue may also appear in other parts of the body, such as the intestines, rectum and bladder.

This tissue, which is similar to the endometrium, acts as it would inside the uterus: it thickens, decomposes and bleeds with each menstrual cycle. But because it has no way of leaving the body, it becomes trapped. This causes a chronic inflammatory reaction, which is why women most often feel pain during menstruation, but the level of discomfort can vary from mild to severe.

Are there any causes of endometriosis?

Although the cause is unclear, the origin of endometriosis is believed to be multifactorial, meaning that its occurrence is due to a combination of many different factors. According to the World Health Organisation (WHO), some of the possible factors of endometriosis2 could include:

  • Retrograde menstruation: when a woman has her period, menstrual blood (containing endometrial cells) flows backwards through the fallopian tubes into the pelvic cavity instead of out of the body through the cervix and vagina.
  • Cell metaplasia: a process in which cells take on a different shape. Some cells outside the uterus transform into endometrial-like cells and begin to grow.
  • Proliferation of precursor cells: they give rise to the disease, which then spreads through the body via the blood and lymphatic vessels.

Other factors are thought to favour the development, growth and maintenance of endometriosis lesions, such as alterations or impairment of the immune system, certain complex hormonal influences, genetic factors and possibly environmental pollutants. The reality is that medicine does not yet have an answer as to what causes endometriosis and this also makes it more difficult to diagnose.

What are the symptoms of endometriosis?

Like any medical condition, a detailed and thorough history is needed if endometriosis is suspected in young women. The severity of endometriosis symptoms and the likelihood of diagnosis increase with age; the incidence peaks in women in their 40s. Only a minority of women (20-25%) do not have symptoms3.

A characteristic symptom is dysmenorrhoea, that is, the presence of pelvic or abdominal pain, particularly during menstrual bleeding and sexual intercourse (dyspareunia). The degree of pain is not associated with the extent of this tissue. A woman may have mild endometriosis with severe pain or she may have advanced endometriosis with little or no pain. So how is endometriosis diagnosed?

Although pain in the lower abdominal area is usually the most common, other symptoms associated with endometriosis may also be a diagnostic sign of endometriosis:

  • Painful urination (dysuria). You are more likely to have these symptoms during a menstrual period.
  • Fatigue, diarrhoea, constipation, bloating or nausea, especially during menstrual periods.
  • Infertility. Sometimes endometriosis is first diagnosed in those seeking fertility treatment.

In addition to symptoms, your doctor may also perform some of the tests that check for physical signs of endometriosis.

Tests to check for the presence of endometriosis

Pelvic examination

During a pelvic examination, the doctor feels areas of the pelvis for abnormalities, such as cysts in the reproductive organs or scars behind the uterus. It is often not possible to feel small areas of endometriosis, unless they have caused a cyst to form.

Transvaginal ultrasound

Although this standard ultrasound imaging test will not definitively tell your doctor if you have endometriosis, it may allow him or her to identify cysts associated with endometriosis (endometriomas).

Magnetic resonance imaging (MRI)

For some cases, an MRI helps with surgical planning by providing detailed information to the surgeon about the location and size of the endometrial ectopic tissue.


Laparoscopy is a surgical procedure used to view the inside of the abdomen (laparoscopy). While you are under general anaesthesia, the surgeon makes a small incision near the navel and inserts a thin viewing instrument (laparoscope), looking for signs of endometrial tissue outside the uterus.

A laparoscopy can provide information about the location, extent and size of endometrial implants or lesions. The surgeon may take a tissue sample (biopsy) for further testing.

Often, with proper surgical planning, the surgeon can fully treat endometriosis during laparoscopy.

What types of treatments and techniques are available for endometriosis?

The decision as to the most appropriate treatment for endometriosis in each patient will depend on the stage of endometriosis. This classification is divided into four stages: I: minimal; II: mild; III: moderate; and IV: severe.

The level of each stage depends on the location, extent and depth of the lesions; the presence and severity of adhesions; and the presence and size (if any) of the ovarian endometrioma. Current treatments include medical, surgical or a combination of these approaches.

Are fertility treatments necessary if you have endometriosis?

Endometriosis can influence fertility in several ways: distorted pelvic anatomy, adhesions, scarred fallopian tubes, inflammation of pelvic structures, altered immune system function, changes in the hormonal environment of the eggs, poor implantation of a pregnancy and impaired egg quality.

If a woman has endometriosis, natural pregnancy may be more difficult to achieve. That is why women diagnosed as infertile are 6-8 times more likely to have endometriosis4.

According to a recent review of the scientific evidence5 , there are three therapeutic options available as therapy for endometriosis-associated infertility: medical treatment, surgery and adapted assisted reproductive technologies, but success rates are variable. There is no single ideal treatment, and it varies depending on the results of the fertility test performed. Your doctor will consider certain factors: the woman’s age, the duration of infertility and pelvic pain.

Medical treatment

Medical treatment with certain therapeutic agents tends to improve pain symptoms, but they generally cause subfertility and are therefore not useful for patients with endometriosis-associated infertility.

Laparoscopic surgery

The aim of surgical intervention is to restore normal pelvic anatomy as much as possible by removing endometriotic lesions and endometriomas. Data from the literature have shown that laparoscopic surgery for minimal to mild endometriosis improves fertility and live birth rates.

In moderate to severe stages, it can treat pelvic adhesions, but unfortunately, there is not enough quality research on the postoperative pregnancy rate. But we should remember the possible disadvantages of this treatment: surgical complications, decreased ovarian reserve, postoperative adhesions, and possible postponement of infertility treatment.

Assisted reproduction techniques after endometriosis

The assisted reproductive techniques used for women with infertility due to endometriosis are intrauterine insemination (IUI) and in vitro fertilisation (IVF).

Intrauterine insemination (IUI) and endometriosis

Patients with minimal to mild endometriosis who have been surgically diagnosed and have not shown any anatomical distortion can improve their chance of pregnancy after controlled ovarian stimulation. This treatment is also called superovulation with IUI. At Eugin we offer you the following types:

However, women suffering from moderate to severe forms of endometriosis do not benefit from IUI due to a likely impact of the lesions on the uterine tubes. In these cases, we recommend the following assisted reproductive treatment.

In vitro fertilisation (IVF) and endometriosis

Currently, IVF is the most successful treatment for women with moderate to severe endometriosis, if all of the above treatments fail to achieve the desired fertility outcome.

But as mentioned above, there is no single ideal treatment for women diagnosed with endometriosis and fertility problems. The management of infertility in patients with endometriosis should be based on the individual circumstances of the patient by a multidisciplinary team.


If you think you may have endometriosis, Eugin can help you and offer you all the information you need about treatment options to help you get pregnant.


  1. New England Journal of Medicine:, Endometriosis Massachusetts Medical Society: Massachusetts Medical Society

  2. Organización Mundial de la Salud: Endometriosis World Health Organization: WHO: Organización Mundial de la Salud

  3. Journal of Assisted Reproduction and Genetics: Endometriosis and infertility University of Firenze, Firenze, Italy: Medicinski Pregled, Croatia

  4. National Library of Medicine: [Infertility and endometriosis] Medicinski pregled: Medicina, Kaunas, Lithuania

  5. National Library of Medicine: Endometriosis Associated Infertility: A Critical Review and Analysis on Etiopathogenesis and Therapeutic Approaches Medicina (Kaunas): Medicina (Kaunas)

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