Often times endometriosis and PCOS can get confused with one another since both of these conditions can affect the reproductive system. However, these conditions are not the same and can affect women differently.
There is one major difference between endometriosis and PCOS. PCOS is a hormonal/metabolic condition with excessive androgens known as testosterone and insulin. Whereas endometriosis is a systemic inflammatory condition.
Endometriosis is when endometrial-like tissue (aka tissue that resembles the lining of the uterus) is found outside of the uterus. It can be found on in and around the reproductive system including the uterus, the fallopian tubes, ovaries, bladder, rectum, legs, pelvic area and intestines. However, the disease has been shown to be found in distant areas such as the lungs and brain.
When it comes to PCOS, some of the major symptoms include irregular cycles, weight gain, and symptoms of high testosterone (ie. hair loss, excessive hair growth, and acne).
If you were wondering whether you have either PCOS or endometriosis here are some of the major differences we see between the two.
As you can see, from the image below, the two conditions are very different but, both can result in long bleeding, spotting, or heavy periods.
When it comes to pain, it is typically a predominant symptom of endometriosis. There can be pain during periods, urination, bowel movements, and during intercourse. That being said, recent research has identified chronic fatigue to be the most common symptom followed by digestive symptoms such as Irritable Bowel Syndrome (IBS)(1).
In PCOS, while pain may be present in the pelvis, pain isn’t always the most predominant symptom we will see.
Lab testing
When it comes to PCOS lab testing, there are many tests to consider. Additionally, a transvaginal ultrasound helps to determine if there are cysts and/or multiple peripheral follicles that surround the ovaries. To see a complete comprehensive list of labs check out this article I wrote.

Lab work cannot be used for a diagnosis of endometriosis. We know that the gold standard for diagnosing endometriosis is laparoscopic surgery. However, sometimes an ultrasound can show endometriosis in the form of an endometrioma aka chocolate cyst on the ovaries. Even though we cannot use lab work for the diagnosis of endometriosis, lab work identifies inflammation and assesses the immune system. For example, we can test for things like Vitamin D status, HS-CRP, cytokines, and antibodies in the thyroid.
Hormones such as estrogen and progesterone can also play a role in endometriosis. We know that estrogen does not cause endometriosis, however, we can see higher levels of estrogen in the system.
Diet
When it comes to diet, PCOS and endometriosis are treated slightly differently. In terms of PCOS, the main focus is to balance insulin and glucose. On the other hand, with endometriosis one of the biggest areas to focus on is to reduce inflammation. We know that one of the most inflammatory foods to the body is gluten. Other foods that can also impact the body in terms of inflammation when it comes to endometriosis include dairy and eggs.
In PCOS, we also want to reduce inflammation however inflammation usually is the result of insulin resistance. So balancing blood sugar is a crucial component when it comes to dietary changes in PCOS.
Summary
PCOS and endometriosis can look similar, however, PCOS is a hormonal condition with excessive androgens known as testosterone. Whereas endometriosis is an inflammatory condition that causes pain.
Next Steps
To learn more about PCOS check out these blog posts.
If you’d like more support, feel free to connect with me here.
Looking for more support? Join Your PCOS Planner HereReferences
1) SIGNORILE, P. G., CASSANO, M., VICECONTE, R., MARCATTILJ, V., & BALDI, A. (2022). Endometriosis: A Retrospective Analysis of Clinical Data from a Cohort of 4,083 Patients, With Focus on Symptoms. In Vivo (Athens, Greece), 36(2), 874–883. https://doi.org/10.21873/INVIVO.12776