Understanding PCOS: Symptoms, Causes, Treatment

Polycystic Ovary Syndrome (PCOS) is one of the most common hormone conditions in women, yet it’s often misunderstood, even by healthcare providers. PCOS affects up to 1 in 5 women of reproductive age and can impact everything from periods and fertility to weight, skin, and mood.

At its core, PCOS is a hormone imbalance driven by the way your body uses insulin. While many people think of PCOS as just a reproductive issue, it’s actually a full-body condition that affects your metabolism, hormones, and long-term health.

Understanding how insulin drives PCOS—and how you can lower it—gives you the power to take control of your symptoms and your future health.

Why Insulin Matters for PCOS

Most people think PCOS is about hormones or weight, but the real driver is insulin. Insulin resistance affects up to 95% of people with PCOS, even those who aren’t overweight. High insulin levels disrupt your hormones, block fat burning, impact fertility, and contribute to common PCOS symptoms like:

Irregular periods
Weight gain
Acne and hair growth
Fatigue and mood changes
Depression and anxiety
Disordered eating

Lowering insulin is the key to improving your symptoms, and your long-term health.

Weight Gain

Why PCOS Makes Weight Loss Hard

Many women with PCOS struggle with weight gain—not because they’re eating too much, but because their insulin levels are too high. Insulin is your body’s main storage hormone. When insulin levels are elevated, your body prioritizes storing energy as fat instead of burning it for fuel. In other words, your body stays stuck in fat storage mode.

This is why women with PCOS often find it harder to lose weight, even when eating the same amount, or less, than someone without PCOS.

High insulin doesn’t just promote fat storage. It also disrupts hormones that regulate hunger and fullness, like leptin and ghrelin. Normally, leptin tells your brain you’re full, while ghrelin signals hunger. Elevated insulin can suppress leptin and increase ghrelin, leading to more hunger, more cravings, and a harder time feeling satisfied after meals.

What’s the solution? While many healthcare providers recommend weight loss to help lower insulin and improve PCOS symptoms, the reality is that meaningful weight loss is almost impossible while insulin levels remain high. That’s why focusing on lowering insulin first—not calories—can make all the difference.

What is Insulin Resistance?

Our Science

Irregular Periods

It Can Make Your Periods Irregular

One of the most common signs of PCOS is irregular or missing periods. This isn’t just a hormone problem, it starts with insulin.

When your diet causes frequent insulin spikes, your body responds by producing more insulin. Over time, this constant demand leads to chronically elevated insulin levels. High insulin disrupts normal hormone signaling. It increases luteinizing hormone (LH) release, preventing regular ovulation. Without ovulation, periods become irregular or stop entirely.

The solution isn’t just managing hormones, it’s lowering insulin. By eating foods that don’t overstimulate insulin, your body can restore ovulation and regulate your cycle, often without the need for hormonal birth control.

So, where do the cysts come from? In a typical menstrual cycle, your ovaries release a mature egg each month. But with PCOS, that process often gets disrupted. Instead of releasing the egg, your body holds onto it, and small fluid-filled sacs, called cysts, can form in your ovaries. These cysts might show up on an ultrasound, which is why the condition is called “polycystic” ovary syndrome.

It’s important to note that not everyone with PCOS has visible cysts. In fact, you can have PCOS without having any cysts at all. That’s because PCOS is really about hormone imbalances, not just the presence of cysts.

Acne

It Can Cause Acne

About half of women with PCOS experience hormonal acne. This is caused by high insulin levels driving up testosterone production.

Higher testosterone levels:

Stimulate your oil glands to produce excess oil
Block pores more easily
Increase skin inflammation

This leads to breakouts, often focused around the jawline, chin, and neck. Managing insulin levels helps lower testosterone and reduce the severity of hormonal acne over time.

Hirsutism

It Can Cause Unwanted Hair Growth

Hirsutism (pronounced HUR-soot-iz-um) refers to the growth of thick, dark, coarse hairs in areas where women typically don’t grow much hair—like the face, chest, back, or lower abdomen. While about 1 in 10 women experience hirsutism, it’s far more common in women with PCOS, affecting up to 75% of them.

Why? Hormones.

Women with PCOS often have elevated levels of androgens—commonly called male hormones—including testosterone. These hormones influence where and how hair grows on the body. Normally, women have fine, soft, non-pigmented hairs called vellus hairs. But when certain hair follicles are exposed to higher levels of testosterone, those vellus hairs can transform into terminal hairs: thicker, darker, and more coarse.

Addressing the underlying hormonal imbalance—particularly by lowering insulin, which drives up testosterone—can help reduce unwanted hair growth over time.

Hair Loss

It Can Cause Hair Loss

While PCOS can cause excess hair in some areas, it can also lead to hair thinning—especially at the crown or hairline. This is known as androgenic alopecia and is linked to high testosterone levels.

When testosterone levels are elevated:

Hair follicles on the scalp shrink
Hair strands become thinner
Hair growth slows over time

By addressing insulin resistance and lowering testosterone, hair thinning can often be slowed, and in some cases, reversed.

Infertility

It Can Make it Difficult to Get Pregnant, and Stay Pregnant

PCOS is a common but treatable cause of infertility in women. Many women with PCOS struggle with irregular ovulation, which means that they may not release an egg regularly. In fact, PCOS is the leading cause of anovulation, with around 80% of women who experience irregular ovulation being diagnosed with PCOS.

Wondering if you’re ovulating? One easy way to track ovulation is by using ovulation predictor kits (OPKs). Additionally, the length of your menstrual cycle can provide some clues. Typically, a cycle longer than 35 days may indicate a lack of ovulation, although it’s not always the case.

Ovulation
One of the biggest reasons women with PCOS struggle to ovulate is high insulin levels. When insulin is too high, it triggers an increase in luteinizing hormone (LH). This throws off your body’s normal hormone rhythm and blocks the LH surge needed for ovulation to happen.
Implantation
Even when ovulation occurs, high insulin can make it harder for a fertilized egg to implant in the uterus. Elevated insulin increases inflammation and oxidative stress in your body, which can interfere with this crucial early step in pregnancy. Insulin can also disrupt other hormones that are important for preparing your uterus for implantation.
Placental Development
Insulin plays a role even after pregnancy begins. High insulin levels can slow or weaken the development of the placenta, the organ that nourishes your baby during pregnancy. This can lead to poor blood flow and reduced oxygen and nutrients reaching your baby, which is believed to increase the risk of miscarriage.
Pregnancy Outcomes
Managing insulin levels before and during pregnancy is important for protecting both you and your baby. High insulin can increase the risk of complications like gestational diabetes, preeclampsia (high blood pressure in pregnancy), and preterm birth. Lowering insulin helps reduce these risks and supports a healthier pregnancy.

Keeping insulin levels low can help your body ovulate more regularly, improve the chances of implantation, and support healthy placenta development. This is important whether you’re trying to conceive naturally or with help from treatments like IVF.

For women with PCOS, high insulin can lower the chances of successful embryo implantation, even during IVF. That’s why lowering insulin first can make a big difference—not just for getting pregnant, but for supporting a healthy pregnancy.

Every fertility journey is different, but managing insulin levels can improve your chances of conceiving and reduce risks during pregnancy. Working with a provider who understands PCOS can help you create a plan that combines treatments with lifestyle changes to support both your health and your baby’s future.

Mood Disorders

It Can Cause Mood Swings

Many women with PCOS experience anxiety, depression, and mood swings. This isn’t just hormonal, it’s metabolic too. High insulin affects your brain chemistry, contributing to unstable mood and low energy.

When insulin levels are high, it can disrupt important brain chemicals called neurotransmitters that control your mood, energy, and emotional balance.

Serotonin
Often called the “feel-good” chemical, serotonin helps regulate your mood, sleep, and appetite. High insulin levels can lower serotonin activity in the brain, making you feel more anxious, irritable, or down.
Dopamine
Dopamine is linked to motivation, focus, and feeling rewarded. When insulin is too high, it can throw off your dopamine balance too, leading to low motivation, mood swings, and symptoms of depression.

This is why managing insulin levels can help stabilize mood and improve mental clarity.

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