Polycystic ovarian syndrome (PCOS) and endometriosis are both conditions that affect women of reproductive age. While it is possible to get pregnant with either diagnosis, both conditions can impact fertility — in addition to the person’s quality of life. 

We spoke with Dr. Shahab Minassian of Main Line Fertility, a renowned expert in the relationship between infertility and PCOS, to help us delve into this topic and unpack what each diagnosis ultimately means for women and their fertility. 

woman consulting with her fertility doctor

What's the difference between PCOS and endometriosis?

The simplest explanation: PCOS is a metabolic disorder, and endometriosis is caused by abnormal cell growth outside of the uterus. 

PCOS occurs when the ovaries and adrenal glands produce too much androgen.

“The AE-PCOS Society, a worldwide organization of PCOS specialists, have published their diagnostic criteria, which includes a combination of irregular periods, elevated androgens, and the finding of polycystic ovaries by ultrasound ovarian changes on ultrasound,” Dr. Minassian explains. “However, women with PCOS may not have all of its symptoms. Hirsutism — or excessive hair growth on the face and body — menstrual irregularities and infertility are the most common.”  

Endometriosis is a condition in which tissue similar to the lining of the uterus (endometrium) grows outside the uterus. It is most commonly found on the ovaries, uterus, fallopian tubes, and lining of the pelvis/abdomen. Endometriosis is primarily marked by chronic pelvic pain and painful, heavy periods.

PCOS, endometriosis, and infertility

“PCOS-related infertility results from a lack of ovulation to sub-optimal ovulation. Lack of proper shedding of the uterine lining every month can lead to overgrowths of tissue and risk for endometrial polyps, which can cause infertility or early miscarriages,” says Dr. Minassian. 

According to Dr. Minassian, weight is often an issue in women diagnosed with PCOS. In fact, insulin resistance is found in at least 70% of PCOS patients, which is why it is recommended by the AE-PCOS Society that all women diagnosed with PCOS have diabetes screening via the 2-hour glucose tolerance test (GTT) as well as a fasting lipid profile and liver enzyme blood testing. Women with abnormal glucose testing are at risk for birth defects in their children, miscarriages, and gestational diabetes. 

PCOS can also cause problems in trying to get pregnant and during pregnancy. Patients with PCOS and weight challenges may have lower pregnancy rates and higher miscarriage rates in treatment.

As for endometriosis, infertile women are more likely to be diagnosed with endometriosis.

woman holding her abdomen in pain

“In its worst form, endometriosis can cause scarring of the fallopian tubes and ovaries, destructive ovarian cysts, and infertility. It can cause egg loss as well as the inability for the egg to be picked up by the tube to get pregnant,” says Dr. Minassian. “Milder cases are frequently not associated with scarring, and it is much more unclear as to why or even whether very mild endometriosis causes infertility.”  

As we know, age has a major effect on pregnancy success rates, and this goes for women diagnosed with either condition, as well. Patients in their mid-30s or beyond generally have lower pregnancy rates and higher miscarriage rates.

PCOS and Endometriosis: Which is “worse” for fertility?

According to Dr. Minassian, in general, significant endometriosis, with tubal and ovarian scarring or cysts, is worse for fertility. For women with bad cases of endometriosis, egg loss is more likely, and that loss cannot be replaced, resulting in reduced chances of getting pregnant, especially with office-based treatments. The inflammation caused by endometriosis can interfere with a woman’s delicate balance of hormones needed to get pregnant. 

Treating PCOS and endometriosis

Most treatments for endometriosis are focused on pain management of symptoms with NSAIDS, hormonal, and non-hormonal medications. While surgery to remove the endometrial tissue from the pelvic organs can be an option, there is no guarantee that it will not grow back. 

Dr. Minassian says office-based infertility treatments for endometriosis can include a combination of fertility medications and intrauterine insemination (IUI). 

For women with PCOS, medications for insulin resistance have helped them achieve natural ovulation, which can be used in tandem with ovulation-stimulating medications. Injectable fertility medications (gonadotropins) can be another treatment option for PCOS patients. Additionally, IVF can be a final treatment option for some women, especially if they do not respond safely to injectable treatments. 

woman giving herself an injection to manage PCOS

“A great way to manage PCOS-related infertility is by lifestyle alterations including diet, exercise, and stress reduction. Diet and exercise should be used together for the best results, and cardio exercise is most effective,” says Dr. Minassian. “'Western’ methods like biofeedback have been advocated, as well as ‘Eastern’ methods like meditation, tai chi, chi kung, and yoga. Anything to reduce the stress that is enjoyable, and therefore can be counted on for long-term use, is advisable. The goals of fertility and a safe pregnancy are now well within reach for women with PCOS.” 

Remember: Whether you have been diagnosed with PCOS or endometriosis, there is still hope to get pregnant. These conditions just limit your chances to do it naturally without any medical intervention. While there are treatments for each condition, make sure you talk with your team of professionals to figure out the best plan of action for you and your needs! 


Brighid Flynn is a freelance writer based in Philadelphia where she lives with her husband and puppy. She is just beginning her journey toward motherhood.