Understanding your PCOS hormones

If you've been diagnosed with PCOS, you've probably heard a string of hormone names thrown at you, insulin, testosterone, LH, FSH, often with little explanation of what they actually mean for your body and your day-to-day life.

This article breaks it down clearly. No jargon, no overwhelm. Just the hormones that matter most in PCOS, why they go out of balance, and what evidence-based steps can help bring them back.

The four hormones you most need to understand

1. Insulin, the root of most PCOS symptoms

Insulin is a hormone made by your pancreas. Its job is to act like a key that unlocks your cells so they can absorb glucose (sugar) from your blood and use it for energy.

In PCOS, many women have insulin resistance, meaning your cells don't respond properly to insulin. Your pancreas compensates by pumping out more and more insulin. Those high insulin levels then trigger your ovaries to produce excess androgens (male hormones like testosterone).

This is why so many PCOS symptoms, weight gain, acne, excess hair growth, irregular periods, trace back to insulin. It's not just about blood sugar. The NHS estimates that insulin resistance affects up to 70% of women with PCOS.

2. Androgens, the hormone behind the visible symptoms

Androgens are often called "male hormones," but women produce them too, just in lower amounts. In PCOS, elevated androgen levels (particularly testosterone and androstenedione) cause many of the most visible and distressing symptoms:

• Excess facial or body hair (hirsutism)
• Acne on the face, chest, or back
• Thinning of the hair on the scalp (female pattern hair loss)
• Irregular or absent periods (androgens disrupt the normal menstrual cycle)

Reducing insulin levels, through diet, movement, and sometimes medication, is one of the most effective ways to reduce androgen production in PCOS.

3. LH and FSH, the signals your ovaries need

LH (luteinising hormone) and FSH (follicle-stimulating hormone) are produced by a small gland at the base of your brain called the pituitary gland. Together they control your menstrual cycle and ovulation.

In women with PCOS, LH levels are often elevated relative to FSH. This imbalance means your ovaries receive the wrong signals. Follicles (small sacs that contain eggs) start to develop but often don't fully mature or release an egg, which is why irregular or absent periods are so common.

The "polycystic ovaries" you see on an ultrasound are actually these partially developed follicles, not true cysts, despite the name.

4. Cortisol, the stress hormone that makes everything worse

Cortisol is your main stress hormone. Short bursts of cortisol are normal and healthy. But chronic elevated cortisol, from ongoing stress, poor sleep, or over-exercising, can worsen insulin resistance and increase androgen production in PCOS.

This is why sleep and stress management aren't just "nice to have" in PCOS, they're part of the hormonal picture.

What can you actually do?

The good news is that lifestyle has a proven, meaningful impact on PCOS hormones. The 2023 International Evidence-Based Guidelines for PCOS, the gold standard for clinical care, recommend lifestyle intervention as the first-line treatment for most PCOS presentations.

Diet and blood sugar balance

Eating in a way that keeps your blood sugar stable is one of the most powerful tools you have. This doesn't mean a strict diet or cutting out entire food groups. It means:

• Pairing carbohydrates with protein, fat, or fibre to slow glucose absorption
• Choosing lower glycaemic index (GI) foods where possible
• Not skipping meals (which can spike cortisol and blood sugar)
• Eating a variety of vegetables, whole grains, legumes, and lean proteins

Movement, but the right kind

Exercise improves insulin sensitivity, meaning your cells respond better to insulin, which reduces the chain reaction that drives androgen excess. Both aerobic exercise (walking, swimming, cycling) and resistance training (weights, pilates, bodyweight) have shown benefits for PCOS.

Critically, more is not always better. Very intense or high-volume exercise without adequate recovery can raise cortisol, which can worsen symptoms. Consistent, moderate movement beats sporadic intense exercise every time.

Sleep

Poor sleep raises cortisol and impairs insulin sensitivity. Research suggests women with PCOS are at higher risk of sleep disorders including sleep apnoea. Prioritising 7-9 hours of quality sleep is genuinely therapeutic, not a luxury.

When medication helps

For some women, lifestyle alone isn't enough, and that's completely valid. Metformin (which improves insulin sensitivity), combined oral contraceptive pills (which reduce androgen production), and other medications have a clear evidence base for PCOS management. These are decisions to make with your doctor, not without.

The bottom line

PCOS is a hormonal condition, but it's not a life sentence. Understanding what's happening in your body, and why, is the first step to feeling less overwhelmed by it.

Insulin resistance drives most of the hormonal imbalances in PCOS. The best tools to address it are the ones you can start today: what you eat, how you move, and how well you rest. Small, consistent changes add up. And you don't have to figure it out alone.