What Is Lean PCOS, and How Do You Treat It?

Polycystic ovarian syndrome (PCOS) is a hormonal disorder caused by excess androgens (hormones such as testosterone and DHEA) produced by either the ovaries or adrenal glands. PCOS is thought to affect up to around 1 in 5 women of reproductive age worldwide. PCOS also affects an unclear number of transgender men and non-binary people.

While many people with PCOS tend to have overweight or obesity, it’s possible to have PCOS and a healthy body mass index, or BMI. This has been described as “lean PCOS.” But “lean” doesn’t mean better: In fact, having lean PCOS can make it harder to get a diagnosis, even though it causes many of the same long-term health complications as other types of PCOS.

So, if you have irregular periods and you’re wondering if you could have PCOS despite a BMI within a healthy range, know that it’s possible.

Here we’ll explore what “lean PCOS” means, how to know if you have it, and how it’s different from other types of PCOS (spoiler: it’s not).

What is lean PCOS?

Lean PCOS is a term for PCOS that affects people who don’t have overweight or obesity (those with a BMI less than 25). 

What are the symptoms of lean PCOS?

The symptoms of lean PCOS tend to be similar to symptoms of non-lean PCOS, although, as we’ll discuss later, there are some differences. In general, people with PCOS can experience the following: 

• Menstrual issues such as irregular or heavy periods, or no periods at all

• Acne

• Excess growth of dark, coarse hairs on areas like the face, thighs, and chest

• Infertility due to not ovulating 

• Insulin resistance, which can lead to abnormal blood sugars and diabetes

Quiz: Could I Have PCOS?

How do you diagnose lean PCOS?

Lean PCOS is diagnosed like other forms of PCOS. There are different ways to diagnose PCOS by different expert groups. Usually the diagnosis is based on having high androgen levels in the blood and menstrual cycle issues. Some experts suggest that an ultrasound showing many cysts on the ovaries (polycystic ovaries) should also be considered as part of the diagnosis, but this isn’t always necessary.

Sometimes other hormone disorders, like an underactive thyroid (hypothyroidism) or Cushing’s disease, can show up similarly to PCOS. Your healthcare provider will check for those, too, with a simple lab test. 

Lean PCOS vs. non-lean PCOS: the same or different?

Anyone can experience a range of symptoms with PCOS, regardless of their weight. For example, one person may have heavy periods and excess hair growth, whereas another may have fertility issues and diabetes. At the same time, two people with totally different BMIs can also have the same symptoms. This is why PCOS can often go underdiagnosed, and even more so if you are lean.

There’s a silver lining though. While people with lean PCOS can still have the same health complications that come with other types of PCOS, diabetes and insulin resistance tend to be less severe. And treatments for ovulation and fertility problems tend to have better results. 

But it doesn’t mean that you’re in the clear just because lean PCOS may not be as severe as non-lean PCOS. You’re still at increased risk of issues like cardiovascular disease, so it’s important that PCOS is taken seriously for everyone.

Much more research is needed to determine how lean PCOS is different from non-lean PCOS, especially since PCOS isn’t a one-size-fits-all diagnosis. 

How do you treat lean PCOS?

The approach for treating PCOS is determined by the symptoms a person experiences, no matter their weight. Here are some examples: 

• Healthy foods and regular exercise help to maintain a healthy weight. The more body fat a person has, the worse their PCOS symptoms can be. 

• Fertility treatments such as clomifene, surgery, or in vitro fertilization (IVF) can help overcome fertility issues. 

• Birth control pills can address menstrual cycle abnormalities.

• Acne treatments such as topical medications (benzoyl peroxide, topical antibiotics, retinoids), and pills (isotretinoin, oral antibiotics, birth control pills) help with this common skin condition. 

• Hair removal such as shaving, laser hair removal, and electrolysis can treat excess hair growth.

• Exercise, metformin, and myoinositol can help manage high blood glucose levels and insulin resistance. 

Together with your healthcare provider, you can figure out what treatments are best for you.

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Written by:

Aunna Pourang, MD

Aunna Pourang, MD, graduated from the University of Florida College of Medicine’s Medical Honors Program and is board-certified in family medicine (Mayo Clinic). She is also fellowship-trained in integrative medicine (Academy of Integrative Health and Medicine).

Edited by:

Sophie Vergnaud, MD

Sophie Vergnaud, MD, is the Senior Medical Director for GoodRx Health. A pulmonologist and hospitalist, she practiced and taught clinical medicine at hospitals in London for a decade before entering a career in health education and technology.

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