Recent research has revealed that the occurrence of early life abuse (whether physical or sexual) is strongly linked to an elevated risk for the development of endometriosis in women.
In fact, the prospective cohort study that examined data from over 60, 000 women over a 24 year period revealed that 79% of those who reported suffering severe, chronic physical and/or sexual abuse in their early years exhibited laparoscopically-confirmed endometriosis as adults1.
While this doesn't mean that everyone who has endometriosis was abused or that everyone who is abused will develop the condition, it is part of a growing body of evidence that adversity experienced in one's early years can lead to health issues later in life.
What is endometriosis?
Endometriosis is a condition wherein tissue similar to that which makes up the lining of the uterus grows outside of it, causing chronic inflammation that leads to the development of scar tissue. Scar tissue adhesions may form throughout the pelvic area, on the ovaries and uterus, organs such as the bladder, as well as the ureters (the tubes through which urine passes from the kidney to the bladder and bowel).
As these adhesions grow, they can cause various areas to stick to one another, stretch or become distorted, leading to chronic pain. In rare cases, endometriosis may spread higher up throughout the body and reach the diaphragm and lungs.
The condition affects approximately 10 to 15% of women globally2. While it can occur at any age during a woman's reproductive years, it is most prevalent in women in their thirties and forties3,4.
Endometriosis symptoms
Not all women have symptoms of endometriosis. In those who do, the primary symptoms include:
- Persistent pelvic pain (this may be dull, throbbing, sharp or burning)
- Dull, crampy pain that begins a few days before menstrual periods (dysmenorrhoea), continues throughout the period and may persist for a few days thereafter.
- Heavy bleeding during menstrual periods
- Pain during ovulation
- Pain during or after sex (dyspareunia)
Other symptoms may include:
- Bladder function issues which may lead to going to increased urination, experiencing increased urgency to urinate or pain during urination5.
- Bowel function issues which may cause cramping, straining, constipation, diarrhoea, or pain during a bowel movement5.
- Lower back pain
- Low energy levels
- Chronic fatigue
- Infertility
Symptoms may occur alone or in combination, and the more symptoms experienced, the more likely it is that a woman may have endometriosis.
How is endometriosis diagnosed?
The condition may be noticeable in imaging (i.e. on CT and MRI scans), however, a definitive diagnosis is usually made during a laparoscopic procedure. This involves a surgeon making a small incision near the belly button, filling the abdomen with gas to inflate it for a better view and inserting a thin, flexible tube with a light and a camera at the end of it (known as a scope) to view the uterus, ovaries, fallopian tubes and nearby organs.
A closer look at the study
The study entitled 'Early life abuse and risk of endometriosis' was funded by the National Institute of Child Health and Human Development and the Atlanta Clinical and Translational Science Institute. It was led by Dr Holly R. Harris, assistant member of Epidemiology at the Fred Hutch's research center and colleagues from Harvard Medical School and Boston's Harvard T.H Chan School of Public Health along with other institutions and was published in the journal Human Reproduction earlier this week.
It was a prospective cohort study which sampled from data from the Nurses Health Study II, or NHSII, an ongoing study that began in 1989 and surveyed nurses aged 24 to 42 on their demographics, medical history, and lifestyle data for over 20 years. Study participants completed a survey questioning them about their exposure to victimisation and violence in 2001.
The research team evaluated data from 116,429 women and found 60,595 who had responded to the survey's childhood abuse questions. Of these, approximately 21% (12,699 women) reported suffering from some degree of physical or sexual abuse during childhood or adolescence.
The next step was to find a correlation between those who had suffered abuse and those who had received a laparoscopically or surgically confirmed diagnosis of endometriosis within this sample. 3,394 women fitted the profile.
Definitions of abuse
For the purposes of the study, physical abuse was defined as follows:
- Mild: If, as a child, the woman was hit with something, punched, kicked or bitten once.
- Moderate: If she was hit with something more than once, or physically attacked in some way.
- Severe: If she was punched, kicked, bitten, endured more than one physical attack, or was ever burned or choked.
The study also characterised sexual abuse as:
- Mild: If the woman experienced any form of sexual touching as a child.
- Moderate: If she was forced to participate in any sexual activity as a child or adolescent.
- Severe: If she was forced into any sexual activity as both a child and adolescent.
Study findings
Of the 3,394 women who had been exposed to some form of either physical or sexual abuse, researchers discovered that women who had experienced multiple types of severe, ongoing abuse had a 79% higher risk of developing endometriosis in comparison to those who reported no exposure to these forms of abuse.
Those who experienced painful symptoms associated with endometriosis were also more likely to have been exposed to severe forms of abuse than those who did not.
The researchers noted that the study was subject to certain limitations and biases as it relied on personal accounts of abuse which may have been misclassified as a result (i.e. when people self-report, they may have perceived an event as less or more serious than it actually was, hence it is not always an accurate representation of the true nature and/or extent of it).
Understanding the association between abuse and endometriosis
Discovering exactly why abuse is associated with the development of endometriosis or any other adverse health outcomes in adulthood is, as Dr Harris describes it, 'a million dollar question'.
The data obtained from the study does, however, give some valuable insights in this area, especially when it comes to the pain experienced due to endometriosis in women who had suffered chronic, severe forms of abuse.
Dr Harris emphasized that the pain experienced was neither imagined nor due to damage or injury caused by sexual abuse in the formative years, but rather that it may be attributed to the stress response induced by traumatic events, which then triggers the body's pain pathway, causing heightened sensitivity to pain.
Harris added that further research to explore the underlying biological mechanisms and the pain pathway is required. The findings in this regard could unlock an entirely new field of treatment for those suffering from chronic pain conditions that may be rooted in abuse.
For now, Harris believes that their newly published study supports existing evidence that the effects of abuse encountered during the early stages of life can have impacts on health that last a lifetime.
References
1. Oxford Academic. July 2018. Early life abuse and risk of endometriosis. Available: https://academic.oup.com/humrep/advance-article-abstract/doi/10.1093/humrep/dey248/5055017?redirectedFrom=fulltext [Accessed 19.07.2018]
2. US National Library of Medicine, National Institutes of Health. January 2017. Parsar, P, Ozcan, P & Terry, KL. Endometriosis: Epidemiology, Diagnosis and Clinical Management. Available: https://www.ncbi.nlm.nih.gov/pmc/articles/PMC5737931/ [Accessed 19.07.2018]
3. The American College of Obstetricians and Gynaecologists. October 2012. Available: https://www.acog.org/-/media/For-Patients/faq013.pdf?dmc=1&ts=20180720T1154442864 [Accessed 19.07.2018]
4. Wiley Online Library. Obstetrics and Gynaecology. April 2017. Epidemiology of endometriosis: a large population‐based database study from a healthcare provider with 2 million members. Available: https://obgyn.onlinelibrary.wiley.com/doi/full/10.1111/1471-0528.14711 [Accessed 19.07/2018]
5. US National Library of Medicine, National Institutes of Health. August 2014. Visceral syndrome in endometriosis patients. Available: https://www.ncbi.nlm.nih.gov/pubmed/24999078 [Accessed 19.07/2018]