7. Juni 20214 Min. Lesezeit

Endometriosis - still an enigma

With the start of the new year we also begin a new collection of articles. This month, we will focus on endometriosis. Endometriosis, such an enigmatic disease that affects up to 15% of women of reproductive age yet there is no cure for it currently. Only a treatment to alleviate the symptoms exists. Endometriosis has significant effects on the social, occupational, psychological, and physiological life of women.

What is it and what are the symptoms? Let’s find out!

Endometriosis is characterized by the presence of functional tissue similar to endometrium (the inner lining of the uterus) outside of the uterus. Endometriosis develops in women of reproductive age and can sometimes regress after menopause or ovariectomy. This suggests that the evolution of endometriosis is estrogen dependent. It is a chronic and relapsing condition that affects up to 15% women of reproductive age, with a peak between 25 and 35 years of age.

This condition is marked by an inflammatory process that is accompanied by the production of new blood vessels, fibrosis (wound healing that turns into a scarred tissue) scarring and anatomical deformation, resulting in pain and infertility.

Endometriosis is classified into 4 categories: stage I (minimal disease), stage II (mild disease), stage III (moderate disease) and stage IV (severe disease). It can even be compared to cancerous cells. Endometriosis is progressive and grows very fast, its growth is estrogen-dependent, can recur even after treatment and has a tendency to metastasize (to spread to other tissues and organs).

Symptoms of endometriosis

1. Pain related to endometriosis

Painful menstruation (dysmenorrhea)
Painful intercourse (dyspareunia)
Painful micturition/urination (dysuria)
Painful defecation (dyschezia)
Lower back or abdominal discomfort
Pelvic pain
Rarely: cyclic leg pain (during menstruation), cyclic rectal bleeding, cyclic dyspnea

2. Infertility

3. Dysfunctional uterine bleeding

4. Gastrointestinal symptoms

5. Urinary tract symptoms

Still, many women are asymptomatic and sometimes symptoms may only develop over time.

Currently, there is no clear explanation as to why endometriosis happens. Suggested mechanisms are retrograde menstruation, immune system abnormalities, genetic causes, environmental and lifestyle factors, prolonged exposure to estrogen (because of first menstruation at an early age, late menopause or obesity), short menstrual cycles, low birth weight. Sometimes endometriosis coexists with other reproductive tract anomalies such as obstruction of menstrual flow or Mullerian anomalies (Mullerian cells are the cells that evolve into the uterus, fallopian tubes, uterine cervix and superior aspect of the vagina).

Factors that can influence endometriosis

1. Lifestyle factors

Even though limited, current research suggests that lifestyle and dietary factors may be associated with the development of endometriosis
A diet high in fruit and vegetables and low in meat products ensures protection against endometriosis
Women with few or no children and low body mass index (BMI) have higher risks in developing endometriosis
Prolonged lactation decreases the risks of developing endometriosis

2. Genetics: Women that have a first degree relative with endometriosis have up to 10 times higher chances to develop it themselves

3. Hormonal factors: nulliparity (when a women has never given birth), subfertility, longer periods between pregnancies

The retrograde menstruation theory

During normal menstruation, menstrual tissue waste, that includes functional cells of the uterine lining, growth factors and proteins, could travel in a retrograde way towards the fallopian tube and pelvic cavity, where the living cells would be able to multiply and invade surrounding tissue
The theory is that women with endometriosis respond to retrograde menstruation as a “wound” that must be healed and as something that has to be removed
While retrograde menstruation occurs in 90% of women (most of the time without negative consequences), endometriosis affects only 10% of these women, therefore other factors such as immune system abnormalities, genetic causes, environmental and lifestyle factors could play an essential role as well
Another finding that dismisses this theory, is the finding of endometrial cells in men undergoing estrogen therapy for prostate cancer
All of these findings seem to suggest that estrogen plays the most significant role in the development of endometriosis

Deeply infiltrating endometriosis

This type of endometriosis refers to endometriosis that infiltrates inside tissues and organs more than 5 mm deep
The symptoms are usually more severe and less treatment options exist
Examples: rectovaginal nodule, bowel invasion, bladder invasion, ureteric invasion, affecting the sciatic nerve (large nerve that runs from the lower back down the back of each leg)

Endometriosis in adolescents

The Endometriosis Association registry reports that 38% of women with endometriosis had symptoms before the age of 15
Adolescents are more likely to present acyclic pain (pain outside the menstruation period) than adult women
It is the second most common cause of dysmenorrhea (primary dysmenorrhea occurs during the first menstruation)

Endometriosis and Cancer

Although endometriosis is a benign disease, it shares many characteristics with malignant (cancerous) diseases
Research shows that there might be a link between endometriosis and ovarian cancer
Endometriosis cells might suffer transformations over time and change into cancerous cells
Based on several studies, women with endometriosis have a significant higher risk (up to 50%) to develop ovarian cancer

With social norms and environmental factors having changed over the last decades (decrease in age for first menstruation, lower number of pregnancies, duration of breastfeeding, delay of first birth), the overall number of ovulations and menstruations a woman has during her reproductive years has increased. Therefore, the likelihood of developing diseases caused by menstruation is greater.

Unfortunately, endometriosis still remains an enigmatic disease that affects too many women. We are rooting for and supporting scientists in their research to find a cure for endometriosis soon.