The main difference between endometriosis and adenomyosis is that in endometriosis, endometrial cells are found outside the uterus, on the ovaries, supporting ligaments of the uterus, as well as in the cavities of the pelvis, whereas in adenomyosis, endometrial cells are found within the wall of the uterus. Furthermore, endometriosis causes pain and may affect fertility while adenomyosis causes thickening of the walls of the uterus, and it has recently been associated with infertility.
Endometriosis and adenomyosis are two disorders in the endometrial tissue, which lines the uterus. Generally, these misplaced endometrial cells follow the menstrual cycle, bleeding monthly.
Key Areas Covered
1. What is Endometriosis
– Definition, Features, Importance
2. What is Adenomyosis
– Definition, Features, Importance
3. What are the Similarities Between Endometriosis and Adenomyosis
– Outline of Common Features
4. What is the Difference Between Endometriosis and Adenomyosis
– Comparison of Key Differences
Adenomyosis, Endometrial Cells, Endometriosis, Fertility, Uterus
What is Endometriosis
Endometriosis is an estrogen-dependent benign inflammatory disease, which is a disorder of the endometrial tissue. Generally, it is characterized by the presence of ectopic endometrial implants mainly in the pelvis or in the upper abdomen. Furthermore, the most common locations of these implants include the ovaries, anterior/posterior cul-de-sac, broad and uterosacral ligaments, uterus, Fallopian tubes, sigmoid colon, and appendix in the descending order. The growth of these implants depends on the steroid hormones produced by the ovaries. Therefore, the disease is more common in women ages 25-35.
Furthermore, the main symptom of endometriosis is asymptomatic infertility. In addition to this, the other symptoms include dyspareunia, dysmenorrhea, bladder/bowel symptoms, and pelvic pain. Moreover, the most definite causes for endometriosis can be retrograde menstruation, coelomic metaplasia, altered immunity, and metastatic spread. Here, retrograde menstruation is the free passage of the endometrial tissue in a retrograde fashion into the peritoneal cavity through Fallopian tubes.
What is Adenomyosis
Adenomyosis is a gynecologic condition of the endometrial tissue of the uterus characterized by the presence of ectopic endometrial tissue within the uterine myometrium. In simple words, the lining of the uterus grows deep into the muscle wall while getting thicker. Therefore, it is also called internal endometriosis. The most common symptom of adenomyosis is, therefore, the heavy as well as more painful menstrual periods.
Moreover, the most definitive etiology of adenomyosis is the disrupted boundary between the deepest layer of the endometrium (endometrium basalis) and the underlying myometrium, causing inappropriate proliferation of endometrial tissue into the myometrium. In addition to this, other causes can be the inappropriate differentiation of pluripotent Mullerian stem cells, altered lymphatic drainage pathways as well as displaced bone marrow stem cells.
Furthermore, biopsy or more often hysterectomy and non-invasive, including ultrasound and MRI can be used for the histological diagnosis of adenomyosis. Generally, the presence of endometrial stroma and glandular tissue within the smooth muscle of the myometrium is the histologic diagnosis of the disease. However, a ‘boggy’ enlarged uterus due to increased vascularization is the classic physical form of examination of adenomyosis.
Similarities Between Endometriosis and Adenomyosis
- Endometriosis and adenomyosis are two fairly common disorders of the endometrial tissue of the uterus.
- Both can occur in older women.
- Moreover, the misplaced cells of the endometrial tissue follow the menstrual cycle.
- Both can affect fertility.
- The etiology of both diseases is not well-known.
- Generally, they are progressive disorders but, treatable and not life-threatening.
- Furthermore, both can result due to the activated stem cells of the endometrium at the end of the tissue injury and repair (TIAR) following trauma to the uterus in an estrogen-dependent manner.
- Other causes include retrograde menstruation, problems with hormones, especially estrogen, problems in the immune and lymphatic systems, and genetic disorders.
- One can have both disorders together.
- Painful periods (dysmenorrhea) and painful sexual intercourse (dyspareunia) are the main symptoms of both disorders.
- Moreover, they can be diagnosed with tissue samples.
- Treatments may vary from the minimal over-the-counter drugs to maximal hysterectomy.
Difference Between Endometriosis and Adenomyosis
Endometriosis refers to a condition resulting from the appearance of endometrial tissue outside the uterus and causing pelvic pain, especially associated with menstruation. However, adenomyosis refers to a condition in which the endometrial tissue breaks through the muscle wall of the uterus, causing menstrual cramps, lower abdominal pressure, bloating before menstrual periods, and heavy periods.
Establishment of the Endometrial Cells
Endometrial cells establish outside the uterus; on the ovaries, supporting ligaments of the uterus as well as in the cavities of the pelvis in endometriosis while endometrial cells establish within the wall of the uterus in adenomyosis.
The most definite causes for endometriosis include retrograde menstruation, coelomic metaplasia, altered immunity, and metastatic spread while the most definitive causes of adenomyosis include the inappropriate proliferation of endometrial tissue into the myometrium, differentiation of pluripotent Mullerian stem cells, altered lymphatic drainage pathways as well as displaced bone marrow stem cells.
Endometriosis occurs in both old and women in the reproductive age, while adenomyosis mainly occurs in older women.
The risk factors of endometriosis include the earlier onset of menstruation, shorter menstrual cycle, taller height, consumption of alcohol and caffeine, etc. On the other hand, the risk factors of adenomyosis include having more than one child, treated with breast cancer, having surgery in uterus, depression, etc.
Other symptoms of endometriosis include painful bowel movements (dyschezia), painful urination (dysuria), pelvic pain, and fatigue, diarrhea, and nausea during periods. In comparison, the other symptoms of adenomyosis include chronic pelvic pain, abnormal or prolonged bleeding during periods, enlarged uterus, and infertility.
Endometriosis causes pain and may affect fertility while adenomyosis causes thickening of the walls of the uterus, and it has recently been associated with infertility.
Basically, endometriosis is a disorder of endometrial tissue that occurs in both old and women in the reproductive age. Misplaced endometrial cells tend to occur outside the uterus, especially, on the ovaries, bladder, intestines, and the cavities of the pelvis. In contrast, adenomyosis is a type of disorder of endometrial tissues which mainly occurs in older women. However, endometrial cells occur inside the wall of the uterus, notably causing heavy periods. Moreover, it is mostly associated with infertility. Therefore, the main difference between endometriosis and adenomyosis is the establishment of misplaced endometrial cells.
1. Macer, Matthew Latham, and Hugh S Taylor. “Endometriosis and infertility: a review of the pathogenesis and treatment of endometriosis-associated infertility.” Obstetrics and gynecology clinics of North America vol. 39,4 (2012): 535-49. doi:10.1016/j.ogc.2012.10.002
2. Gunther R, Walker C. Adenomyosis. [Updated 2019 May 14]. In: StatPearls [Internet]. Treasure Island (FL): StatPearls Publishing; 2019 Jan-. Available Here.
1. “Blausen 0349 Endometriosis” By BruceBlaus – Own work (CC BY 3.0) via Commons Wikimedia
2. “Adenomyosis MRI” By Case courtesy of Dr Varun Babu, Radiopaedia.org, rID: 43504 – Case courtesy of Dr Varun Babu, Radiopaedia.org. From the case rID: 43504 (CC BY-SA 4.0) via Commons Wikimedia