Hypothyroidism or PCOS? The Difference Every Woman Must Know

If you’re consistently feeling tired, gaining weight, experiencing irregular periods, or breaking out unexpectedly, it could be a sign of hormonal imbalances. However, which hormones are causing these issues?

Hypothyroidism and polycystic ovary syndrome (PCOS), two common culprits, share many overlapping symptoms, making diagnosis challenging. Consequently, many women are misdiagnosed or treated for the wrong condition, often leading to years of inadequate care.

“Since both conditions mess with hormone balance, it’s easy to confuse them,” says Dr. Jolene Brighten, a naturopathic physician and women’s health expert. “But they have different causes and need different treatments.”

Let’s break down what makes hypothyroidism and PCOS similar, different, and how to figure out which one might be affecting you—or if you could have both.

The Hormone Basics

• Hypothyroidism happens when your thyroid gland doesn’t produce enough thyroid hormone (T3 & T4). This slows down your metabolism and affects nearly every organ in your body.
• PCOS is a metabolic and hormonal disorder where the ovaries produce excess androgens (male hormones), leading to issues with ovulation, insulin resistance, and inflammation.

Shared Symptoms (And Why They Confuse Doctors)

Symptom	Seen in Hypothyroidism	Seen in PCOS
Fatigue	✅	✅
Weight gain	✅	✅
Irregular periods	✅	✅
Depression/anxiety	✅	✅
Fertility struggles	✅	✅
Dry skin/hair loss	✅	Sometimes
Acne	Rare	✅
Cold intolerance	✅	❌
Hair growth on face/body	❌	✅

Because they share these symptoms, it’s easy to be told “you’re just tired” or “it’s stress” when in reality, your hormone panel is screaming for attention.

The Key Lab Tests

Getting the right labs is crucial for diagnosis. Here’s what your doctor should order:

For Hypothyroidism:

• TSH (Thyroid Stimulating Hormone)
• Free T3
• Free T4
• Anti-TPO Antibodies (to rule out autoimmune Hashimoto’s)

Normal TSH doesn’t always mean your thyroid is healthy. Look at Free T3/T4 for better insight.

For PCOS:

• Total Testosterone
• Free Androgen Index
• LH:FSH Ratio
• DHEA-S
• Fasting insulin/glucose
• Ultrasound (to check for ovarian cysts)

Polycystic Ovary Syndrome (PCOS) isn’t solely determined by the presence of cysts in the ovaries. It’s a condition that encompasses a combination of symptoms and lab markers, rather than relying solely on ultrasound examinations.

Root Cause Differences

Factor	Hypothyroidism	PCOS
Hormone involved	Low thyroid (T3, T4)	High androgens (testosterone, DHEA)
Primary driver	Autoimmunity (often Hashimoto’s)	Insulin resistance + inflammation
Metabolism	Slows down	Often disrupted due to insulin
Menstrual effect	Long, light, or missing periods	Irregular, heavy, or absent periods
Fertility issue	Ovulation doesn’t happen reliably	Ovulation is delayed or absent

Can You Have Both? Yes—And Many Women Do

In fact, up to 22% of women with PCOS also have hypothyroidism, particularly autoimmune Hashimoto’s.

If you’ve been diagnosed with PCOS and still experience persistent exhaustion or coldness, Dr. Brighten suggests considering testing your thyroid as well.

Treatment Looks Different

Hypothyroidism

• Thyroid hormone replacement (usually levothyroxine or natural desiccated thyroid)
• Anti-inflammatory diet
• Addressing nutrient deficiencies (selenium, iodine, zinc)

PCOS

• Blood sugar balancing diet (low-glycemic, anti-inflammatory)
• Supplements like inositol, NAC, omega-3s
• Exercise and stress management
• Sometimes metformin or hormonal birth control

When to See a Doctor

If you’re dealing with:

• Persistent fatigue or low mood
• Irregular cycles
• Weight gain despite exercise
• Excess hair or acne
• Fertility struggles

Ask your doctor for a comprehensive hormone panel, not just a basic TSH test. Consider both PCOS and thyroid function as potential causes, especially if you’ve only been diagnosed with one.

Advocate for Yourself

PCOS and hypothyroidism, two conditions that affect millions of women, are often overlooked or misdiagnosed. However, with the right lab tests, a knowledgeable healthcare provider, and a personalized treatment plan, you can regain balance and feel like yourself once again.

“You know your body best. If something feels off, don’t settle for vague answers,” says Dr. Brighten.