PCOS and Fertility: Why Cutting Calories and Doing More Cardio Isn’t Helping
The Common PCOS Weight Loss Myth
“If you want to get pregnant, you need to lose weight. And to lose weight, you need to eat less and exercise more.”
Sound familiar?
It’s the advice women with PCOS hear all the time—from doctors, from the internet, from well-meaning friends and family. But here’s the truth: PCOS doesn’t work like that.
In fact, over-restricting food and over-exercising can make PCOS symptoms worse, not better. Instead of helping with weight loss and fertility, these habits can increase stress on the body, throw hormones further out of balance, and make it even harder to conceive.
So, if you’ve been cutting calories and pounding the treadmill without results, it’s not your fault. Your body isn’t broken—it just needs the right support. Let’s talk about why traditional weight loss advice fails women with PCOS and what actually works instead.
Why “Eat Less, Move More” Doesn’t Work for PCOS
Most weight loss advice is based on the calories in, calories out model. But women with PCOS don’t metabolise food the same way as women without it. Here’s why:
1. Insulin Resistance Makes Weight Loss More Complex
Up to 70-80% of women with PCOS have insulin resistance, meaning their bodies struggle to use insulin properly. This leads to higher insulin levels, which trigger the ovaries to produce more testosterone—disrupting ovulation and making it harder to lose weight.
So when women with PCOS dramatically cut calories, their blood sugar levels become even more unstable, causing:
❌ Increased cravings and energy crashes
❌ More fat storage, especially around the belly
❌ Hormonal imbalances that make ovulation irregular
In other words, eating too little can actually make PCOS symptoms worse—not better.
2. Over-Exercising Increases Stress Hormones
You might think that more exercise = more weight loss, but for women with PCOS, too much high-intensity exercise can work against you.
Excessive cardio (like daily running or HIIT) increases cortisol, your body’s main stress hormone. When cortisol is high for too long, it can:
❌ Increase insulin resistance (making weight loss harder)
❌ Suppress ovulation (making pregnancy more difficult)
❌ Cause the body to hold onto fat instead of burning it
That’s why pushing harder in the gym won’t necessarily help you lose weight or get pregnant faster. Your body needs a different approach—one that supports your hormones instead of working against them.
Why Cutting Calories Can Harm Your Fertility
Most women with PCOS are told that weight loss will improve their fertility. And while losing weight can help, it’s how you do it that matters.
Undereating = Nutrient Deficiencies = Poor Egg Quality
When you cut calories too aggressively, you’re likely missing out on key nutrients like:
Healthy fats (needed for hormone production)
B vitamins (essential for ovulation)
Protein (important for egg quality)
Over time, nutrient deficiencies can lead to irregular cycles, poor egg health, and lower chances of conception.
Too Few Calories = Stress Mode = Ovulation Shutdown
Your body is smart. When it senses you’re not getting enough food, it thinks:
⚠️ “Food is scarce. This is not a good time to have a baby.”
As a result, it reduces reproductive function to save energy. That means:
Ovulation becomes irregular (or stops completely)
Progesterone levels drop (increasing the risk of miscarriage)
Fertility naturally declines
This is why fertility-friendly nutrition is about nourishing your body—not depriving it.
The Problem with Too Much Cardio
There’s nothing wrong with exercise—it’s one of the best things you can do for PCOS. But not all exercise is created equal.
If you’re doing hours of cardio every week and not seeing results, here’s why:
1. Excessive Cardio Can Increase Inflammation
Long, intense workouts can cause more stress than your body can recover from, leading to:
❌ Higher cortisol (stress hormone) levels
❌ Increased inflammation (which worsens PCOS symptoms)
❌ Muscle loss instead of fat loss
2. Cardio Alone Doesn’t Build Metabolism-Boosting Muscle
Strength training helps build lean muscle, which naturally boosts insulin sensitivity and makes it easier to regulate weight. But too much cardio without strength training can actually lead to muscle loss, slowing your metabolism down over time.
3. Over-Training Can Worsen Hormonal Imbalances
Excessive exercise can reduce progesterone levels, leading to:
Irregular cycles
More PMS symptoms
Lower fertility
If you’re working out harder and harder but not seeing changes, your body may be in a stress state—which means it’s holding onto weight instead of burning it.
What to Do Instead: A PCOS-Friendly Approach to Weight Loss and Fertility
So if cutting calories and over-exercising don’t work, what does?
✅ Balance Blood Sugar
Instead of focusing on calorie restriction, shift your focus to stabilising blood sugar levels. This means:
Prioritising protein at every meal
Pairing carbs with fibre and healthy fats
Eating regularly to prevent blood sugar crashes
✅ Move in a Way That Supports Ovulation
The best types of exercise for PCOS and fertility include:
Strength training (builds metabolism-boosting muscle)
Walking (lowers cortisol and improves insulin resistance)
Yoga & Pilates (reduce stress and support hormone balance)
✅ Fuel Your Body Instead of Depriving It
Your body needs enough food—not just the right kinds. Make sure you’re getting:
Enough calories to support hormone production
Healthy fats to improve egg quality
Key nutrients like iron, zinc, and vitamin D for fertility
✅ Prioritise Stress Management & Sleep
Aim for 7-9 hours of sleep per night
Reduce stress with mindfulness, journaling, or gentle movement
Swap high-intensity workouts for restorative activities when needed
Final Thoughts: Your Body Isn’t Broken
If you’ve been eating less, exercising more, and still struggling with PCOS symptoms, it’s not because you’re not trying hard enough. It’s because your body needs a different kind of support.
Instead of punishing your body, focus on nourishing it. Support your hormones, balance your blood sugar, and move in a way that helps—not hurts—your fertility.
And if you need personalised guidance on your journey from PCOS to pregnant, I’m here to help.
💛 Click here to book a free call and let’s chat about how my PCOS to Pregnant Protocol can help you take back control of your fertility—naturally.