PCOS vs. Endometriosis: What Are the Differences?

Endometriosis and polycystic ovary syndrome (PCOS) are both linked to hormonal imbalances and can lead to infertility. However, these two conditions affect female reproductive organs differently.

PCOS primarily affects the ovaries and is linked to excess male sex hormones called androgens. Endometriosis is associated with higher levels of the female hormone estrogen. It can affect the ovaries, the uterus, and other organs in the lower abdominal cavity, such as the bladder and intestines.

A photo illustration with information about PCOS vs. Endometriosis

Photo Illustration by Zack Angeline for Verywell Health; Getty Images

Approximately 11% of people with a uterus are diagnosed with endometriosis. Between 4% and 20% of people assigned female at birth are diagnosed with PCOS. Both occur during the childbearing years.

This article explains the differences between PCOS and endometriosis. It also discusses the symptoms of each and how they are diagnosed and treated.

How to Know if It's Endometriosis or PCOS

Although endometriosis and PCOS share symptoms, they are different conditions. Endometriosis causes chronic pelvic pain, while PCOS is a metabolic disorder.

What Is Endometriosis?

The innermost lining of the uterus is called the endometrium. The endometrium helps keep the uterus functioning properly, especially during pregnancy. When the endometrial tissue begins to grow outside the uterus, it's called endometriosis. Endometriosis is the most common cause of pelvic pain in people of childbearing age.


What Is PCOS?

PCOS occurs when the ovaries and adrenal glands produce too much androgen hormone, called hyperandrogenism.

The ovaries have several important functions, including the release of reproductive hormones. The growth and release of an egg from the ovary (ovulation) depend on those reproductive hormones.

In addition, cysts (fluid-filled sacs) form in the ovaries of most people with PCOS.



Endometriosis and PCOS have a few common symptoms, including irregular menstrual periods and infertility. However, several differences set them apart.

  • Diabetes and insulin resistance

  • Fluid-filled sacs in the ovaries

  • Excess body and facial hair

  • Infertility

  • Infrequent menstrual cycles

  • Male-pattern baldness

  • Masculine features

  • Obesity

  • Severe acne

Endometriosis is primarily marked by chronic pelvic pain and painful, heavy periods. It can also cause bladder, bowel, and sexual dysfunction.

Signs of PCOS are more systemic. In addition to infrequent periods, the hormonal imbalance in PCOS leads to excess hair growth on the face and body (hirsutism), severe acne, and male pattern baldness.

PCOS is a metabolic disorder. It commonly presents along with excess body weight, obesity, diabetes, insulin resistance, and acanthosis nigricans—patches of thick, velvety, darkened skin on the neck and skin folds associated with insulin resistance.

Causes and Risk Factors

Although hormonal imbalances play a part in endometriosis and PCOS, other causes and risk factors are unique to each condition.


It's unclear what causes endometriosis, but possibilities include retrograde menstruation (menstrual blood flowing in the wrong direction), genetics, impaired immune system, increased estrogen levels, and abdominal surgery (endometrial tissue can be transferred to other organs during surgery).

Endometriosis risk factors include:

  • Early menarche (before age 11)
  • Family history of endometriosis (mother or daughter)
  • Short monthly periods (27-day cycle or less)
  • Heavy menstrual bleeding
  • Infertility
  • High estrogen levels
  • Alcohol use (increases estrogen levels)


Although the exact reason why PCOS occurs is not fully understood, experts agree that it is a complex endocrine condition with multiple causes, including diet and lifestyle factors.

Fat cells also release androgens, which is why it's not uncommon for obese people to experience PCOS. Hyperandrogenism also leads to insulin resistance and diabetes.

Additionally, irregular menstrual cycles and multiple cysts in the ovaries lead to infertility. PCOS is one of the most common causes of female infertility, affecting 70% to 80% of people wanting a pregnancy.

Risk factors for having PCOS include:

  • Obesity
  • Diabetes
  • Epilepsy
  • Hyperandrogenism
  • Family history of PCOS
  • Premature puberty (before age 8 or 9)

Is There a Link Between Endometriosis and PCOS?

A study found that although endometriosis and PCOS share abnormalities in hormonal balance, body weight, age of menarche (when periods start), and reproductive irregularities, the causes of those abnormalities differ. Therefore, a link between the two gynecologic disorders cannot be made.

Can You Have Both?

Although rare, people can have both endometriosis and PCOS. Such reported cases show that endometriosis is often mild when found in combination with PCOS.


Endometriosis and PCOS require several tests to confirm their diagnosis. Endometriosis often takes longer to diagnose than PCOS.

Diagnosing Endometriosis

The following are ways to diagnose endometriosis:

  • Pelvic exam: Identifies masses, cysts, and areas of pain.
  • Imaging tests: A pelvic ultrasound can help find cysts in the ovaries, while magnetic resonance imaging (MRI) recognizes endometriosis by taking pictures of organs and tissues.
  • Laparoscopy: A surgery that looks in your abdominal cavity to find signs of endometriosis. The surgeon may diagnose endometriosis by visualizing the invading tissue; however, a biopsy (removing a sample of tissue to be examined in a lab) may be required to confirm the diagnosis.

Your healthcare provider may give you medications that help decrease estrogen levels. If medications relieve your symptoms, you likely have endometriosis.

Diagnosing PCOS

The following are ways to diagnose PCOS:

  • Physical exam: Identifies increased body mass index (BMI), and signs of other conditions that could be responsible for PCOS symptoms
  • Pelvic exam: Feeling for enlarged ovaries
  • Pelvic ultrasound: Helpful in finding ovarian cysts
  • Blood work: Checks for increased androgen levels, thyroid disease, diabetes, and cholesterol level

Your healthcare provider will also review a history of your menstrual cycles and fertility.


Medications, surgery, and lifestyle changes can improve the symptoms and quality of life for people with endometriosis or PCOS.

How Endometriosis Is Treated

Treatment for endometriosis is often geared toward pain management. However, considering the person's desire for pregnancy is also important.

  • Medications: Nonsteroidal anti-inflammatory drugs (NSAIDs) are used first to decrease inflammation and alleviate discomfort. Hormonal medications such as Myfembree (relugolix, estradiol, and norethindrone acetate) and Orilissa (elagolix), and non-hormonal medications (aromatase inhibitors) can help reduce pain and inflammation.
  • Surgery: Removal of the uterus, fallopian tubes, and ovaries may be necessary to alleviate the symptoms of endometriosis. In addition, removing endometrial tissue from other organs (bladder, colon) may also be an option. Unfortunately, it's not uncommon for endometriosis to recur (come back) after surgery.
  • Lifestyle: A study found that cooking with clean ingredients, eating more fresh fruits and vegetables, and decreasing gluten and dairy improved endometrial symptoms. This study was supported by other research indicating a healthy lifestyle can improve both the physical and mental challenges of endometriosis.

How PCOS Is Treated

Treatment of PCOS is tailored to decrease the symptoms and reduce the long-term health implications caused by it, which include diabetes and cardiovascular disease. The following are ways to treat PCOS:

  • Medications: Oral contraceptives and antiandrogens help alleviate PCOS symptoms and reduce androgen levels. However, increased androgen levels lead to health complications such as insulin resistance, diabetes, increased cholesterol levels, and heart disease. Metformin may help treat those side effects.
  • Lifestyle: Making lifestyle changes is the first-line treatment for PCOS. Losing 5% to 7% of body weight can produce a regular menstrual cycle, improving pregnancy chances. Anxiety and depression are prevalent in people with PCOS. An improved lifestyle and sense of well-being have improved the quality of life for those with PCOS.

When to See a Healthcare Provider

Call your healthcare provider for the following symptoms:

  • Heavy, irregular, or absent periods
  • Chronic pelvic pain
  • Masculine traits
  • Infertility


Endometriosis and PCOS are different gynecologic disorders but are both chronic conditions that are difficult to manage.

Endometriosis occurs when endometrial tissue travels outside the uterus and damages other organs. PCOS, however, occurs when androgen levels are abnormally elevated, and multiple cysts are found in the ovaries. PCOS results in masculine features and infertility.

Endometriosis and PCOS are managed with medications, surgery, and lifestyle changes. Although treatable, neither condition is curable.

A Word From Verywell

Endometriosis and PCOS can be frustrating conditions to manage. Fortunately, they rarely occur together, but each disorder can negatively affect your quality of life.

Although living a healthy lifestyle can alleviate the symptoms of endometriosis and PCOS, having a sense of well-being also improves these conditions. It's essential to have social support in addition to medical help when living with endometriosis or PCOS.

Frequently Asked Questions

  • Can endometriosis cause you to gain weight?

    No. Endometriosis does not usually cause weight gain; most people with this condition are average or underweight.

  • Can PCOS trigger endometriosis?

    PCOS and endometriosis are not linked and do not trigger one another.

  • Is PCOS an autoimmune disease?

    PCOS is not considered an autoimmune disease; it is the most common endocrine disorder in women.

  • What is the best diet for PCOS and endometriosis?

    A diet of natural ingredients and rich in fresh fruits and vegetables improves symptoms of endometriosis and PCOS. Exercising also improves quality of life.

  • Can PCOS cause cancer?

    PCOS has been shown to increase the risk of developing certain types of cancer, such as endometrial cancer.

  • Can PCOS and endometriosis cause infertility?

    PCOS and endometriosis have high rates of infertility. About 30% to 50% of people with endometriosis are infertile, and 70% to 80% of people with PCOS experience infertility.

19 Sources
Verywell Health uses only high-quality sources, including peer-reviewed studies, to support the facts within our articles. Read our editorial process to learn more about how we fact-check and keep our content accurate, reliable, and trustworthy.
  1. Centers for Disease Control. Polycystic ovary syndrome.

  2. Office on Women's Health. Endometriosis.

  3. Deswal R, Narwal V, Dang A, Pundir C. The prevalence of polycystic ovary syndrome: a brief systematic reviewJ Hum Reprod Sci. 2020;13(4):261. doi: 10.4103/jhrs.JHRS_95_18

  4. The American College of Obstetricians and Gynecologists. FAQs: Endometriosis.

  5. The American College of Obstetricians and Gynecologists. FAQs: Polycystic ovary syndrome.

  6. Abraham Gnanadass S, Divakar Prabhu Y, Valsala Gopalakrishnan A. Association of metabolic and inflammatory markers with polycystic ovarian syndrome (PCOS): an update. Arch Gynecol Obstet. 2021;303(3):631–43. doi:10.1007/s00404-020-05951-2

  7. National Institutes of Health. What are the risk factors for endometriosis?

  8. Peterson CM, Johnstone EB, Hammoud AO, et al. Risk factors associated with endometriosis: importance of study population for characterizing disease in the ENDO StudyAmerican Journal of Obstetrics and Gynecology. 2013;208(6):451.e1-451.e11.  doi: 10.1016/j.ajog.2013.02.040

  9. Khan MJ, Ullah A, Basit S. Genetic basis of polycystic ovary syndrome (pcos): current perspectivesAppl Clin Genet. 2019;12:249-260.  doi:10.2147/TACG.S200341

  10. Melo A, Ferriani R, Navarro P. Treatment of infertility in women with polycystic ovary syndrome: approach to clinical practiceClinics. 2015;70(11):765-769. doi:10.6061/clinics/2015(11)09

  11. Sirmans S, Pate K. Epidemiology, diagnosis, and management of polycystic ovary syndromeCLEP. doi:10.2147/CLEP.S37559

  12. Dinsdale NL, Crespi BJ. Endometriosis and polycystic ovary syndrome are diametric disordersEvol Appl. 2021;14(7):1693-1715. doi:10.1111/eva.13244

  13. Office of Women's Health. Polycystic ovary disease.

  14. Rafique S, Decherney AH. Medical management of endometriosisClinical Obstetrics & Gynecology. 2017;60(3):485-496. doi:10.1097/GRF.0000000000000292

  15. Singh SS, Suen MWH. Surgery for endometriosis: beyond medical therapiesFertility and Sterility. 2017;107(3):549-554. doi:10.1016/j.fertnstert.2017.01.001

  16. ennberg Karlsson J, Patel H, Premberg A. Experiences of health after dietary changes in endometriosis: a qualitative interview studyBMJ Open. 2020;10(2):e032321. doi:10.1136/bmjopen-2019-032321

  17. Rocha AL, Oliveira FR, Azevedo RC, et al. Recent advances in the understanding and management of polycystic ovary syndrome. F1000Res. 2019;8:565. doi: 10.12688/f1000research.15318.1

  18. National Institutes of Heath. Can PCOS lead to cancer?

  19. Bulletti C, Coccia ME, Battistoni S, Borini A. Endometriosis and infertilityJ Assist Reprod Genet. 2010;27(8):441-447. doi:10.1007/s10815-010-9436-1

By Serenity Mirabito RN, OCN
Serenity Mirabito, MSN, RN, OCN, advocates for well-being, even in the midst of illness. She believes in arming her readers with the most current and trustworthy information leading to fully informed decision making.