One study found that individuals with PCOS are 8x more likely to be diagnosed with endometriosis than those without the condition,[1] a condition where tissue that is similar to the inner lining of the uterus grows outside of the uterus.[2]

Endometriosis results in a chronic inflammatory reaction but its exact cause is unknown.[3]  PCOS is a complex systemic disorder caused by a complex interplay of genetic, epigenetic and environmental factors.

A potential link between PCOS and endometriosis is based on the link to elevated estradiol,[4] a hormone that acts as a growth hormone for the reproductive organs.[5]

PCOS is associated with elevated levels of androgens[6], sex hormones that are produced in the ovaries, start at puberty and play a key role in reproductive health.[7]  Find out more about PCOS and Androgen Excess.

• High androgen levels lead to elevated cytokine levels, the small molecules that control the growth an activity of other immune cells;[8]

• Elevated cytokine levels result in higher pro-inflammatory signals, an increased immune response that normally works to protect your body from viruses, bacteria, allergens and other harmful substances;[9],[10]

• Higher inflammatory signals lead to endothelial dysfunction, where the single cell layer that lines the blood vessels constricts or narrows when they should be dilating or opening;[11],[12] and

• This endothelial dysfunction is linked to endometriosis, with regression of this dysfunction in patients following surgical treatment.[13]

  
  

Other studies have characterized endometriosis and PCOS as diametrically opposite disorders.[14]  Endometriosis has been linked to exposure to low levels of testosterone in the womb[15] in contrast to the hereditary risk of PCOS due to elevated levels of testosterone.

There are a number of common symptoms to PCOS and endometriosis, including pelvic pain, heavy menstrual bleeding and infertility.[16],[17]  These shared symptoms are a complicating factor in diagnosing one or both of these conditions.

There are a variety of other risk factors for endometriosis, including:[18]

•     Not having given birth;

•     Sharing your period early or going through menopause late;

•     Short menstrual cycles;

•     Heavy bleeding and prolonged menstruation;

•     Elevated levels of estrogen;

•     Low body weight; and

•     Close family history of endometriosis.

Reviewed by Riya Ganguly PhD., MBA, ICD.D, expert on technology transfer, new venture development and research facilitation

PARTNER SPOTLIGHT

Gynica is a women's health biotechnology company, dedicated to developing a non-hormonal, intravaginal, cannabinoids-based drug for the treatment of Endometriosis - a debilitating condition that affects one in ten women and girls of reproductive age, with over 200 million women and girls suffering worldwide.

Sources

[1] https://academic.oup.com/jcem/article/100/3/911/2839432

[2] https://www.mayoclinic.org/diseases-conditions/endometriosis/symptoms-causes/syc-20354656

[3] https://www.who.int/news-room/fact-sheets/detail/endometriosis

[4] https://www.sciencedirect.com/science/article/abs/pii/S1001784412600133

[5] https://www.news-medical.net/health/What-does-Estradiol-do.aspx

[6] https://www.uptodate.com/contents/polycystic-ovary-syndrome-pcos-beyond-the-basics/

[7] https://my.clevelandclinic.org/health/articles/22002-androgens

[8] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9103656/

[9] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9103656/

[10] https://my.clevelandclinic.org/health/body/24585-cytokines

[11] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC9103656/

[12] https://stanfordhealthcare.org/medical-conditions/blood-heart-circulation/endothelial-dysfunction.html

[13] https://pubmed.ncbi.nlm.nih.gov/24777848/

[14] https://www.ncbi.nlm.nih.gov/pmc/articles/PMC8288001/

[15] https://pubmed.ncbi.nlm.nih.gov/34659773/

[16] https://www.medicalnewstoday.com/articles/endometriosis-vs-pcos#symptoms

[17] https://journals.sagepub.com/doi/abs/10.5301/je.5000181?journalCode=peva

[18] https://www.mayoclinic.org/diseases-conditions/endometriosis/symptoms-causes/syc-20354656