Endometriosis: A Narrative Review


  • Andrew Zakhari, MD Obstetrics & Gynecology, McGill University, Montreal, QC Minimally Invasive Gynecologic Surgery MUHC EndoCARES, Royal Victoria Hospital, McGill University Health Centre (Glen Site)
  • Dong Bach Nguyen, MD Obstetrics & Gynecology, McGill University, Montreal, QC Endometriosis and Minimally Invasive Gynecologic Surgery MUHC EndoCARES, Royal Victoria Hospital, McGill University Health Centre (Glen Site)




Although much progress has been made since endometriosis was first scientifically described centuries ago, numerous unanswered questions still surround this chronic, inflammatory condition. For instance, one theory on the pathogenesis of endometriosis suggests that the condition begins from retrograde menstrual flow implanting on surfaces in the abdomen and pelvis (Samson’s theory), which is a logical mechanism given the high rates of endometriosis in patients with obstructive anomalies of the lower genital tract and significant retrograde flow. This explanation has many shortcomings however, as retrograde menstruation occurs more commonly than the reported 10% prevalence of endometriosis. Additionally, endometriosis lesions can be found in areas quite remote from the pelvis, such as the thoracic cavity. As such, research has been increasingly focused on identifying immune, genetic, and local environmental factors that likely play critical roles in the development of endometriosis. This growth of benign endometrial-like tissue outside of the uterus can sometimes be asymptomatic, but it can also cause debilitating pain, infertility, ovarian cysts (endometriomas), and can invade surrounding organs such as the bowel or bladder. There are three main phenotypes of endometriosis: superficial lesions, deeply infiltrating endometriosis (including nodules), and ovarian endometriomas.

While the exact etiology may be obscure, the societal and economic impacts of this condition are undeniable. Patients diagnosed with endometriosis are at a significantly higher risk of absenteeism from work or school, lower quality of life, chronic pelvic pain, and are more likely to receive a mental health diagnosis such as depression or anxiety. Apart from direct and indirect incurred costs to patients (estimated at approximately $5000 per patient annually), at a national level the economic burden of endometriosis exceeds $2 billion annually in Canada, and approaches $80 billion in the USA. 

Author Biographies

Andrew Zakhari, MD, Obstetrics & Gynecology, McGill University, Montreal, QC Minimally Invasive Gynecologic Surgery MUHC EndoCARES, Royal Victoria Hospital, McGill University Health Centre (Glen Site)

Dr. Andrew Zakhari completed his medical degree at McGill University in 2013 followed by postgraduate training in Obstetrics and Gynecology at the same institution. Since that time, he has completed a two-year fellowship at Toronto's Mt. Sinai Hospital in Advanced Gynecologic Surgery, while pursuing a Masters in Global Surgical Care from the University of British Columbia. Dr. Zakhari has a strong interest in complex surgical cases such as advanced endometriosis and invasive placentation and is actively involved in undergraduate and postgraduate medical education at the McGill University Health Centre Royal Victoria Hospital, where he joined as staff in 2020.

Dong Bach Nguyen, MD, Obstetrics & Gynecology, McGill University, Montreal, QC Endometriosis and Minimally Invasive Gynecologic Surgery MUHC EndoCARES, Royal Victoria Hospital, McGill University Health Centre (Glen Site)

After obtaining his medical degree at McGill University, Dr. Dong Bach Nguyen completed a 5-year residency in Obstetrics and Gynecology at the same institution. He then pursued a 2-year fellowship in Minimally Invasive Gynecologic Surgery at the Ottawa Hospital, under the American Association of Gynecologic Laparoscopists. This was further complemented by international fellowships in Bordeaux, France, at the Franco-European Multidisciplinary Institute of Endometriosis and at the Institut Bergonié – the former focusing on advanced bowel and urological endometriosis, and the latter, on complex surgeries for gynecological cancers. Dr. Nguyen is currently an Assistant Professor at McGill University and an Obstetrician/Gynecologist at the McGill University Health Centre. His practice is focused on complex surgeries to treat conditions such as endometriosis, uterine fibroids, ovarian cysts, and placenta accreta spectrum disorders. He is one of the founding members of the MUHC EndoCARES, a surgical referral center for women with multi-organ endometriosis. Apart from his clinical duties, Dr. Nguyen also holds a fellowship in Education by Simulation from the Department of Innovation in Medical Education, and is actively involved in post-graduate medical education, clinical research, and quality improvement in women’s healthcare.


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How to Cite

Zakhari, A., & Nguyen, D. B. (2024). Endometriosis: A Narrative Review. Canadian Women’s Health Today, 1(2), 23–28. https://doi.org/10.58931/cwht.2024.1213