PCOS vs. Endometriosis: Causes, Treatments & How To Advocate For Yourself

When I first got my period at age 11, I thought I might be dying because of the horrid stabbing sensation. A decade later, I was finally diagnosed with endometriosis. Later still, tests confirmed a constellation of cysts on my ovaries, and doctors suspected I also had polycystic ovary syndrome, or PCOS, though I lacked many of the classic signs.

"PCOS is a hormonal disorder that causes imbalances leading to enlarged ovaries and cysts1, irregular periods, and excess androgen levels, such as testosterone," says Shoma Datta-Thomas, M.D., an OB/GYN head of wellness at Modern Age.

PCOS affects 1 in 102 people assigned female at birth, meaning it's not rare. "PCOS is the most common endocrine condition in women during their reproductive years," says Nadia C. Brito Pateguana, B.Sc., N.D., with The Fasting Method. However, the World Health Organization reports that up to 70% of people with PCOS remain undiagnosed3.

Endometriosis is a chronic and painful inflammatory condition that is dependent on estrogen. Recently, the UK's National Health Service listed endometriosis as one of the top 20 most painful conditions.

The endometrium is tissue that lines the uterus and is shed each month during one's period. With endometriosis, tissue that "acts" like the endometrium16 implants on tissue outside the uterus.

There it forms lesions, or growths, on other tissues and organs. Since the lesions act like the endometrium, they respond to menstrual cycle hormones and bleed during one's period. The resulting internal bleeding can lead to scar tissue and adhesions, which can cause tissue and organs to "stick" together. For example, the bladder and uterus may become attached to each other.

"Something we've spent a lot of time on in the last several years is reimagining endometriosis as a systemic whole-body disease that affects multiple organs," says Hugh Taylor, M.D., a developmental biology professor and chair in the Department of Obstetrics, Gynecology, and Reproductive Sciences at Yale School of Medicine.

"It's not just a few lesions in the pelvis. It may start in the pelvis, but it has so many ramifications throughout the entire body that there's almost no organ that isn't affected," Taylor adds. Lesions also secrete proteins called pro-inflammatory cytokines17, leading to inflammation and pain, which can be debilitating.

In order to diagnose PCOS, doctors use a combination of pelvic imaging, blood tests, and other exams. "It is a syndrome and a diagnosis of exclusion, which requires extensive testing," says Pateguana. A diagnosis of exclusion means doctors must rule out other potential causes of symptoms first.

Endometriosis has historically been diagnosed with laparoscopic surgery16—a small camera is inserted into the abdomen to look for lesions. However, this isn't the only diagnostic method we have, and some physicians (like Taylor) advocate for nonsurgical diagnosis35.

"We can make a presumptive diagnosis by listening to our patients and considering all these symptoms and putting the pieces of the puzzle together," he says. "If you wait to require surgery to make a definitive diagnosis, you're waiting until somebody's really miserable. And that's just cruel in my mind. It's really held people back for years and disrupted their lives before they get adequate treatment."

People often experience delays of multiple years in receiving a diagnosis for endometriosis and PCOS36.

Why is that? For endometriosis, researchers note a lack of health care provider knowledge and a lack of adequate research funding37 for the condition. The National Institutes of Health designated less than 0.1% of research funding38 to studying endometriosis in 2022.

Let's not forget that patients with PCOS and/or endometriosis also report not having their symptoms taken seriously when they take them to their doctors. Medical gaslighting, which women are disproportionately affected by, is common with both conditions.

I remember one doctor, in 2007, despite clear surgical evidence (from multiple procedures) of my endometriosis, walked into my hospital room and said, "Don't you think it's all up here?" while she pointed to my head.

Endometriosis and PCOS are two different chronic conditions with different causes and symptoms, though some overlap. Endocrine-disrupting chemicals are implicated as a potential cause in both conditions, for example. And fertility issues are another commonality.

According to recent research, both conditions involve disruption39 of the hypothalamic-pituitary-ovarian axis. The HPO axis is the feedback loop that controls the menstrual cycle. This disruption may occur in utero to the fetus. 

The short answer is yes39, according to research and all the experts I interviewed for this article. Both endometriosis and PCOS are common conditions. Researchers aren't sure how common it is for these conditions to coexist, but they do.

A key difference between the two is that estrogen drives endometriosis, while testosterone drives PCOS. "High testosterone levels can actually suppress endometriosis," Taylor says. "But they're not usually high enough in PCOS to do that. Not everyone with PCOS has very high testosterone levels. And there's usually enough estrogen around in PCOS to grow endometriosis as well."

Fertility issues are common to both endometriosis and PCOS. However, various treatments and strategies can help boost fertility.

"Endometriosis' effects on fertility are not completely understood but likely involve inflammatory pathways and anatomic damage," Datta-Thomas says. "It may cause scarring and affect the reproductive organs, which has an impact on fertility for many women."

Surgery31 may be necessary to remove lesions and address anatomical issues. And additional fertility assistance may be necessary. "If endometriosis has scarred the tubes, then a woman will often need IVF," says functional gynecologist Wendie Trubow, M.D., MBA.

"The conventional treatment for PCOS," Pateguana says, "is the birth control pill to help regulate cycles and other Band-Aid treatments to treat each symptom (there are often many symptoms and expressions) as well as fertility treatments to attempt successful pregnancy, but none of the current conventional treatments reverses PCOS."

Ultimately, the latest research shows that addressing and managing insulin resistance is key since it's such a huge factor in PCOS. Plus, we have natural ways of managing insulin resistance. To become more insulin sensitive, which is a good thing, Pateguana has some advice.

"The main tip is to focus on reversing metabolic syndrome and lowering insulin through fasting and a low insulin diet (aka low carb)," she says. A ketogenic diet has been shown to be helpful43 in managing symptoms, for example.

Some people choose to wear a continuous glucose monitor to track blood sugar, keep their glucose levels more stable, and learn what foods cause glucose spikes. (I did this for a month and the experience was eye-opening, especially for the banana and oat milk I used to put in my smoothie!) High blood sugar drives insulin resistance. However, mitigating blood sugar spikes helps to reverse insulin resistance, which could help with PCOS.

Typically, the goal of treatment involves pain management and maintaining the health of various organs, especially in the pelvis.

"The first-line treatment is birth control," Taylor says, "not because it's the best or greatest but because it's easy and people are familiar with it." Hormonal birth control helps in about one-third of people with endometriosis, according to Taylor.

"But there are a lot more people who have side effects from birth control pills," he adds. "For about half of women, it either doesn't work to relieve pain, or they stay on it because it's helping with the pain, but they feel terrible in other ways."

Another medication used to treat endometriosis is Lupron, which induces medical menopause. However, Taylor notes the issues with this medication, which was frequently prescribed in the past45. It has fallen somewhat out of favor now. He describes it as "a very harsh injectable drug that's slow to act and actually can, for the first couple of weeks, make the disease worse before it gets better."

I personally took one injection of this medication in 2002, and it was a horrid experience that required me to take a quarter off graduate school.

Also under the list of medication treatments is gonadotropin-releasing hormone agonists46, or GnRHa meds. "Orilissa and Myfembree are the brand names that are of a milder or gentler form that are oral, that work right away." These drugs reduce estrogen levels to help combat endometriosis, he explains.

A host of medications may also be prescribed to help manage pain, including anticonvulsants and pelvic floor Botox. Meds, such as antidepressants47, may also be prescribed to help manage the mental health symptoms endometriosis causes.

Many people with endometriosis require surgery to remove lesions and endometriomas and to fix anatomical issues. Anatomical issues can involve adhesions48 that are causing organs to stick together or issues like an incarcerated uterus49. An incarcerated uterus is when the womb is retroverted50, meaning it's tipped backward and is stuck in that position. Endometriosis lesions can cause a uterus to become incarcerated.

Finally, lifestyle changes may also help manage endometriosis. Eating an anti-inflammatory diet may be of benefit51, for example. Sugar itself and high-carbohydrate diets drive inflammation, as do ultra-processed foods. Eating whole, organic foods may be able to help and support your gut microbiome and therefore your immune system.

Both Trubow and Pateguana are also advocates for acupuncture to help with endometriosis pain. Although we need more research on acupuncture, one small study noted a 62% reduction in pain52 for participants with endometriosis.

Finally, if you have pain with sex, talk to your doctor about it. They may be able to refer you to a physical therapist who can help with pelvic floor dysfunction53, which is linked to endometriosis.

Whether you have endometriosis, PCOS, or both conditions, the importance of advocating for yourself at the doctor's office cannot be understated. The first thing to know is that symptoms aren't in your head, and, no, you shouldn't just have to deal with the pain or other issues.

Taylor acknowledges the "demeaning" things the medical community has said to people assigned female at birth with these conditions. He wants people to know that menstrual cramps should not change or get worse over time. If your doctor is dismissing your symptoms, he advocates for speaking up or finding a doctor with expertise in endometriosis or PCOS if possible.

PCOS and endometriosis are both extremely common—but unfortunately, difficult to get a proper diagnosis for. As covered in this piece, there are some key differences between PCOs and endometriosis but also a few similarities, and they can both exist simultaneously in rare cases. If you suspect you have either or both, share your symptoms with your doctor. As Jennifer's experience shows, finding the right treatment plan can be a long and frustrating journey. Know that you're not alone—and many people are suffering from the same symptoms. Visit our Invisible Illness series for more advice on advocating for yourself when you have a chronic health condition.

Endometriosis and PCOS are both common conditions that can wreak havoc on whole-body health and well-being. They can occur separately or together, and neither has a cure. However, some treatments can help with condition management.

Researchers acknowledge we need better treatments, and that symptoms from these conditions should be taken seriously and addressed. Unfortunately, not all doctors, even OB/GYNs, are knowledgeable about endo or PCOS. Thus, people assigned female at birth are often left to advocate for themselves.