By Dr. Colin Michie FRCPCH
This condition is frequent: It can affect over 10% of women in their childbearing years. It is a long-lasting problem too, that can damage the quality of life of those suffering with it. Globally, endometriosis is thought to be the most common cause of pelvic pain and excessive period bleeds in women. It often causes infertility – half the women investigated for infertility are found to suffer with endometriosis. Many women suffer in silence with this condition, others perhaps accept it as a “demonic curse”; but treatments are available.
Normally, endometrial cells remain within the womb. The womb or uterus where the foetus implants and grows is lined by the endometrium. Endometrium cells change steadily during the menstrual cycle of about four weeks (it can vary from 21-35 days). These cells proliferate and mature, encouraging a rapid growth of blood vessels prior to ovulation. If a fertilised embryo has not implanted into this thickened carpet of supportive tissues, they are then all shed, along with their blood vessels, as menstrual blood. A sequence of powerful hormones drives this elaborate process, from the woman’s ovaries and the pituitary gland.
Endometrial cells respond to hormonal messages – they remain vital communicating systems. And the menstrual cycles involve the immune system, too. When the endometrium is ready to accept a precious bundle of foetal cells for implantation, it attracts immune cells to protect against infection. Further, if foetal cells begin implantation, immune cells in the endometrium need to protect them and help to build the placenta. Immune protections are needed to allow these cells to be tolerated in the endometrium and uterus.
Endometriosis is the uncontrolled and progressive growth of womb-lining tissues outside the uterus. These cells may, rarely, start their misdirected colonisation before menstruation starts in young women; they can show themselves after the menopause, when menstruation has stopped. They are most often found on the ovaries, but can migrate to anywhere in the abdominal cavity, growing on its lining, the peritoneum. Endometrial cells outside the uterus have the capacity to enhance new blood vessels and recruit stem cells from the bone marrow as well as immune cells. These form masses of tissue that may become inflamed. Most lesions are less than 6cms across when diagnosed.
Endometriosis can grow deep in the pelvis between the gut, womb and bladder. Because of this anatomy, it can cause pain on intercourse or on passing urine. It can also be found in the lungs. A recent study from Martinique found that endometriosis was more frequent than expected as a cause of chest problems, including releasing air or blood into the lung cavities.
The gold standard for diagnosing endometriosis is visualising and identifying these tissues outside the uterus. Open surgery is now rarely used; typically, a laparoscopic examination of the abdominal cavity is employed. Ultrasound and magnetic resonance imaging are useful tools; blood-testing systems are being explored.
A biological puzzle with endometriosis is to explain why endometrial cells might develop outside the uterus. No genetic directions have been found. And connected with this are practical questions: How can a woman with symptoms of pelvic pain or infertility be safely and quickly investigated? If she is found to have endometriosis, what methods can be used to treat her symptoms?
Although there is currently no cure, medical and surgical treatments exist for endometriosis. Advice and careful monitoring are important because each woman ideally requires personalised care. Treatments depend on whether infertility is an issue for her. Crucially endometrial cells require oestrogen hormones to grow – these rogue cells respond to hormonal messages. Medical approaches can involve anti-inflammatory or hormonal strategies directed at this dependency. For instance, Levonorstrel (used in the morning-after pill) may be delivered as an intrauterine device. A progesterone compound, dienogest, has been found effective too, as may a combined oral contraceptive. Such treatments are often required for several years.
However, for women planning to conceive, different approaches are likely to be useful. These will often include plans involving egg collection and assisted pregnancy methods, such as in vitro fertilisation. New medical therapies with stem cells and a number of regulatory molecules are being developed and tested. Surgical strategies may be appropriate to remove or ablate endometrial masses. These need to include discussion relating to preserving ovarian function.
Endometriosis challenges the reproductive health of our communities. Little about this condition is straightforward, starting with the difficulties faced by women describing and communicating their invisible problem to doctors. Taboos and stigmas relating to menstrual health persist – recognising this medical problem by all of us can aid sufferers. Endometriosis has been declared a public health priority by French health authorities; a UK parliamentary enquiry has directed supportive systems be designed. Research innovations and investments need these encouragements. There are needs here to be met, and there is hope.
Useful resources:
https://www.nhs.uk/conditions/endometriosis/
https://www.who.int/news-room/fact-sheets/detail/endometriosis
Dr. Colin Michie specialises in paediatrics, nutrition, and immunology. Michie has worked in the UK, southern Africa and Gaza as a paediatrician and educator and was the associate Academic Dean for the American University of the Caribbean Medical School in St. Maarten a few years ago.
