Polycystic Ovarian Syndrome and Nutrition


PCOS is a hormonal disorder affecting millions of women around the world. The exact cause of PCOS is unknown, and it is theorized that different issues within the body could influence the manifestation of PCOS. PCOS is influenced by genetics, environment, nutrition, and the functional health of your whole body (1). Improving your nutrition and overall health can have a ripple effect of positive improvements in your PCOS.

What is PCOS?

PCOS stands for Polycystic Ovarian Syndrome. The keyword here is syndrome.

A syndrome is “a condition characterized by a group of symptoms that consistently occur together.”

In other words, we don’t why it happens, but it happens often enough to give it a name!

1 in every 10 women have PCOS but many women go years before receiving the diagnosis (2). One of the reasons for this is that the symptoms vary person to person. You and your best friend can both have PCOS and each have a different set of visible symptoms. Some of the symptoms of PCOS like weight gain, acne, and irregular periods may even be dismissed as “normal,” further delaying an accurate diagnosis.

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What are the criteria for a PCOS diagnosis?

There are two sets of criteria for diagnosing PCOS. The Rotterdam criteria and the Androgen Excess and PCOS Society Criteria.

The Rotterdam Criteria

If your doctor uses the Rotterdam Criteria, there are 3 big signs they will check when investigating a PCOS diagnosis (3).

  1. Multiple cysts on your ovaries

  2. High levels of blood androgens (testosterone)

  3. Irregular periods

You need two of these signs for a doctor to consider a PCOS diagnosis. Any combination can get you a PCOS diagnosis.

It is entirely possible to have elevated blood androgens and irregular period, but no cysts show up on an ultrasound. This also means a doctor will not diagnose PCOS on ultrasound findings alone.

Having multiple cysts does not necessarily indicate that you have the condition.

The Androgen Excess and PCOS Society Criteria

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This criteria requires the presence of excess androgens as a diagnostic criteria (4). You must have all three of these criteria to get a PCOS diagnosis.

  1. Excess androgens in a blood test.

  2. Other reasons for excess androgens have been excluded.

  3. Ovarian dysfunction (not ovulating) or polycystic ovaries.

This set of criteria differs from the above Rotterdam Criteria by requiring the presence of excess androgens for a diagnosis of true PCOS. For example, with the more general Rotterdam criteria you could receive a PCOS diagnosis with multiple cysts and irregular cycles only. There are many other reasons those two symptoms could occur together that are not linked with PCOS.

For example, a teenager who is producing 25 follicles per month and who is under emotional stress from exams and physical stress from competitive sports could certainly have a few anovulatory cycles and have multiple cysts visible on an ultrasound. However, her scenario is likely temporary and not indicative of true PCOS.

How is PCOS diagnosed?

Blood Tests

Excess androgens is one of the hallmarks of PCOS. But it is not something you can observe. Your doctor will order a blood test in order to determine your levels. They likely will also test your other hormones. Always get a copy of your lab results for your personal records. It is helpful to keep this information in one place and monitor your progress over time. There are many doctors and practitioners who can help you manage your PCOS, and you are ultimately the one in control of your own health.

Common blood test your doctor might order:

  • Free testosterone - Less than 4% of total testosterone circulates as free, bioavailable testosterone. This is considered the best test for identifying a condition (5).

  • Total testosterone - This tests for the total quantity of testosterone in the blood. It does not show how much of the testosterone is circulating freely and how much is bound to SHBG. It is helpful to also test for SHBG if testing total testosterone to get a clearer picture. SHBG may be low in women with PCOS (6).

  • SHBG (Sex Hormone Binding Globulin) - SHBG binds to both testosterone and estrogen and transports the inactive forms of these hormones through the blood stream.

  • Androstenedione - Androstenedione is produced by the ovaries and the adrenal glands. It is a precursor (building block) to make testosterone and estrogen. Androstenedione may be higher in women with PCOS (7).

  • DHEA-S - DHEA-S is the sulfated version of DHEA. This means the molecule DHEA has a sulfur group attached to it, which makes it inactive. A test for DHEA itself is an indicator of the body’s response to an immediate stressor and the test for DHEA-S is a better indicator of the body’s total, life-long storage level of DHEA (8). DHEA-S is produced exclusively in the adrenal glands (9).


PCOS cannot be diagnosed by ultrasound alone (10). An ultrasound is used to see the multiple cysts that PCOS is named for. It will look like a string of pearls around the edge of your ovary. It is possible to have PCOS and not find cysts on an ultrasound. And it is possible to find multiple cysts and not have PCOS. Due to the nature of the menstrual cycle (it is always changing!) the ultrasound will look different every month.

Cycle Charting

Irregular cycles are very common among women in general. While it is common - it is not ideal. Tracking your monthly cycle is the best way to get a clear picture of your hormonal health.

At minimum, track the length of your period and overall cycle length.

If you suspect a hormonal imbalance or are trying to become pregnant with PCOS, consider tracking cervical mucus and basal body temperature in addition to your period and cycle length. This will give you a far clearer picture of your hormonal health.

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How do multiple cysts form in PCOS?

Each month Follicle Stimulating Hormone (FSH) stimulates the ovaries to develop follicles. Each follicle contains an immature egg. What’s supposed to happen is that the follicle grows, the egg matures, signals are sent from the ovary to the pituitary saying that the egg is ready. The pituitary responds with hormones that trigger ovulation. The follicle releases the egg during ovulation, then the follicle transforms into a corpus luteum which begins producing progesterone.

In a woman with PCOS these follicles stop developing. The result is that the hormonal signaling that tells the pituitary the egg is ready are not sent, and so ovulation does not occur. The underdeveloped follicles go on to become small cysts which are eventually reabsorbed. If you have an ultrasound done in the later part of your cycle, you may be able to see these cysts. They look like a string of pearls on the side of your ovary.

Why do women with PCOS have irregular periods?

First, it’s important to know what a normal cycle looks like for you. The 28 day cycle is a myth. Anywhere between 26-33 days is healthy. It’s important to monitor your own cycle to know what is regular for you. For example, if you cycle is usually 29 days and suddenly it’s 33 days, that is irregular for you, even though 33 days is a healthy cycle length.

Women with PCOS often have very long cycles, over 33 days, or skip periods completely.

It is often the lack of ovulation that causes irregular cycles. The body will wait a few extra days for ovulation to occur. When ovulation doesn’t happen, eventually you will menstruate but your cycle has already been extended by a few days or weeks.

High testosterone levels can also make it hard for your body to menstruate. This can make your cycle even longer.

What causes increased androgens?

The ovaries naturally produce a small amount of androgens. This is perfectly normal and healthy. Androgens help increase libido and mood. But when androgen levels are too high they create negative side effects.

Androgens include testosterone, DHEAS (the combination of DHEA and DHEA-S), and androstenedione.

Androgens are produced in the ovaries and adrenal glands. It’s important to remember that these endocrine glands, the ovaries and adrenals, do not act on their own free will. They act in response to direction from the pituitary gland. These organs function through feedback loops that are finely tuned based on functions throughout the entire body. There are multiple reasons androgens can increase, including chronic stress, insulin resistance, use of hormonal birth control, and chronic inflammation. It is important to take a whole-body approach and seek the root cause when managing PCOS.

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Mollie Williams