Understanding the Differences Between PCOS and Endometriosis
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Understanding the Differences Between PCOS and Endometriosis

Endometriosis and Polycystic Ovary Syndrome (PCOS) are two common conditions that affect women during their reproductive years. Both disorders can cause significant pain and complications, including infertility. Despite their similarities in impacting female reproductive health, they have distinct differences in symptoms, causes, diagnosis, and treatment. This detailed blog will explore these differences to provide a comprehensive understanding of both conditions.

Endometriosis vs. PCOS: An Overview

Endometriosis is a condition where endometrial-like tissue grows outside the uterus, commonly affecting the ovaries, fallopian tubes, and the tissue lining the pelvis. This tissue continues to act as it normally would—thickening, breaking down, and bleeding with each menstrual cycle. However, because this tissue has no way to exit the body, it becomes trapped, leading to pain, cyst formation, and adhesions.

PCOS is a hormonal disorder characterized by the presence of multiple small cysts on the ovaries and elevated levels of male hormones (androgens). This condition can disrupt the normal menstrual cycle, leading to irregular periods, and may cause symptoms such as excessive hair growth, acne, and obesity.


Endometriosis Symptoms:

  • Chronic pelvic pain
  • Painful periods (dysmenorrhea)
  • Pain during or after sex
  • Painful bowel movements or urination, particularly during menstruation
  • Heavy menstrual bleeding or bleeding between periods
  • Fatigue, diarrhea, constipation, bloating, and nausea
  • Infertility

PCOS Symptoms:

  • Irregular menstrual cycles or absence of menstruation (amenorrhea)
  • Excess hair growth on the face and body (hirsutism)
  • Severe acne
  • Male-pattern baldness or thinning hair
  • Weight gain and difficulty losing weight
  • Dark, thickened skin patches, often on the neck, groin, and under the breasts
  • Infertility
  • Ovarian cysts

Causes and Risk Factors


The exact cause of endometriosis is not well understood, but several factors may contribute:

  • Retrograde menstruation: Menstrual blood flows backward into the pelvic cavity instead of leaving the body.
  • Genetics: A family history of endometriosis can increase the risk.
  • Immune system disorders: Problems with the immune system may make the body unable to recognize and destroy endometrial-like tissue outside the uterus.
  • Hormonal imbalances: High levels of estrogen can promote the growth of endometrial tissue.
  • Surgical scars: After surgeries like a C-section or hysterectomy, endometrial cells may attach to the surgical incision.


The exact cause of PCOS is also unclear, but factors that may play a role include:

  • Genetics: PCOS tends to run in families.
  • Insulin resistance: High levels of insulin can increase androgen production, leading to difficulties with ovulation.
  • Inflammation: Low-grade inflammation can stimulate polycystic ovaries to produce androgens.
  • Hormonal imbalances: Excess androgens and low levels of sex hormone-binding globulin (SHBG) disrupt normal ovulation.


Endometriosis Diagnosis:

  • Pelvic exam: Doctors check for cysts or scars behind the uterus.
  • Ultrasound: Imaging tests can identify cysts associated with endometriosis.
  • Magnetic resonance imaging (MRI): Provides detailed images of the body's internal structures.
  • Laparoscopy: A surgical procedure where a camera is inserted into the abdomen to look for endometrial tissue outside the uterus. A biopsy may be performed for confirmation.

PCOS Diagnosis:

  • Physical exam: To identify symptoms like hirsutism and high BMI.
  • Pelvic ultrasound: To detect cysts on the ovaries.
  • Blood tests: To measure hormone levels, including androgens and insulin.


Endometriosis Treatment:

  • Medications: Pain relievers like NSAIDs and hormonal therapies (birth control pills, GnRH agonists, and progestins) to reduce symptoms.
  • Surgery: Laparoscopic surgery to remove endometrial tissue or, in severe cases, hysterectomy (removal of the uterus).
  • Lifestyle changes: Dietary adjustments, such as reducing gluten and dairy, and incorporating more fruits and vegetables can help manage symptoms.

PCOS Treatment:

  • Medications: Birth control pills to regulate menstrual cycles, anti-androgens to reduce symptoms like hirsutism, and diabetes medications like metformin to manage insulin resistance.
  • Lifestyle changes: Weight loss through diet and exercise can help regulate insulin levels and improve ovulation.
  • Fertility treatments: Medications like clomiphene can stimulate ovulation.

Key Differences and Similarities

Both conditions can cause menstrual irregularities and infertility but differ significantly in their primary symptoms and underlying hormonal imbalances. Endometriosis is primarily associated with estrogen dominance and severe pelvic pain, while PCOS involves androgen excess and metabolic issues like insulin resistance.

Can You Have Both?

While rare, it is possible for someone to have both endometriosis and PCOS. Managing both conditions simultaneously requires a comprehensive approach tailored to address the unique symptoms and health challenges posed by each disorder.


Endometriosis and PCOS are both complex conditions that require proper diagnosis and management to improve quality of life. Early diagnosis and a combination of medical treatments and lifestyle changes can help manage the symptoms effectively. If you suspect you have either condition, consulting with a healthcare provider is essential for proper evaluation and treatment planning. Understanding the differences between PCOS and endometriosis is the first step towards better health and well-being.

  • Endometriosis vs PCOS: Differences and Similarities Explained; American University of the Caribbean School of Medicine
  • PCOS vs. Endometriosis: What Are the Differences? Verywell Health
  • Polycystic Ovarian Syndrome and Endometriosis as Two Evil Extremes of Health Continuum; J Reprod Infertil. 2022
  • The pathogenesis of endometriosis: molecular and cell biology insights. Int J Mol Sci. 2019. Dinsdale N, Nepomnaschy P, Crespi B. The evolutionary biology of endometriosis. Evol Med Public Health. 2021
  • A systematic review of anogenital distance and gynecological disorders: endometriosis and polycystic ovary syndrome. Front Endocrinol (Lausanne). 2021
  • Coexistence of polycystic ovary syndrome and endometriosis in women with infertility. J Endomet Pelvic Pain Disord. 2014
  • Variation among human populations in endometriosis and PCOS A test of the inverse comorbidity model. Evol Med Public Health. 2021
1.Endometriosis vs. PCOS: An Overview
3.Causes and Risk Factors
6.Key Differences and Similarities
7.Can You Have Both?