What Is PCOS Actually Doing Inside Your Body?

By Tina Chagoury, Clinical Dietitian · 5 min read · 2026-09-28

Being told you have polycystic ovary syndrome without being told what it means is one of the most common experiences in women's health.

You were told you have polycystic ovary syndrome, and you did not really understand what that meant. That is an extremely common experience, so let me explain what is genuinely happening inside your body.

Start with the normal cycle

In a typical cycle, a follicle in the ovary matures and releases an egg. That release is ovulation. After it, the remaining structure produces progesterone for the second half of the cycle.

Progesterone is the calming, regulating hormone. It settles the nervous system, supports sleep, regulates the immune response and balances oestrogen.

What happens in PCOS

In PCOS, that maturation process is disrupted. Multiple follicles begin to develop but frequently none completes the process, so ovulation does not reliably occur.

Two consequences follow immediately.

Without ovulation, there is no meaningful progesterone. Which means the calming, balancing hormone is largely missing, cycle after cycle.

Androgens rise. These are the hormones associated with acne, unwanted hair growth and hair thinning at the scalp.

That is why the classic presentation is irregular or absent periods, acne, elevated androgens and disrupted ovulation.

The part that gets underplayed: insulin

For a large proportion of women with PCOS, insulin resistance is central rather than incidental.

Elevated insulin drives the ovaries to produce more androgens. More androgens further disrupt ovulation. Disrupted ovulation means no progesterone. And insulin resistance itself makes weight gain easier and weight loss considerably harder.

It is a loop, and insulin is frequently the point at which it can be broken.

This is why blood sugar work is central to PCOS management, and why so many women find that everything improves at once when they address it rather than treating each symptom separately.

Why it is not always the same condition

PCOS is not one presentation. Some women have significant insulin resistance and metabolic features. Others do not. Some are diagnosed on ultrasound appearance, others on symptoms and bloodwork.

Which is why a single generic PCOS diet does not exist, and why anyone offering one is oversimplifying.

What actually helps

Regardless of the presentation, these are the foundations:

• Stabilise blood sugar. Protein at every meal, three structured meals, no all day grazing, carbohydrate eaten with protein and fibre rather than alone.
• Build muscle. Resistance training improves insulin sensitivity through a pathway that does not depend on insulin at all. For PCOS this is one of the highest yield interventions available.
• Reduce the inflammatory load.
• Support the gut, because gut inflammation and hormone clearance both matter here.
• Sleep and stress, because cortisol worsens the insulin picture directly.

What to test

Fasting glucose and fasting insulin together so HOMA-IR can be calculated, HbA1c, a full androgen panel, a complete thyroid panel, vitamin D, ferritin and inflammatory markers.

And if you are approaching your forties, know that PCOS does not disappear with age. It changes shape, and the metabolic side usually becomes more prominent rather than less.

This article is nutrition education, not medical advice. PCOS diagnosis and management belong with your doctor or gynaecologist.

Tina Chagoury is a licensed clinical dietitian specialising in women's hormonal health, and the creator of the Hormone Reset Method™. Learn more and start here.