PMOS (PCOD/PCOS) vs Thyroid: How These Two Conditions Are Connected
By Femly Health Editorial Team · 24 September 2026
Yes, you can have PMOS (PCOD/PCOS) and a thyroid disorder at the same time. Both are common hormonal conditions. They often share symptoms like irregular periods, weight changes and tiredness. Research shows the two conditions can occur together, but they do not cause one another. Doctors usually check for both when a woman has these symptoms.
What Are PMOS and Thyroid Disorders?
PMOS, or polycystic ovary syndrome, is a hormonal condition that affects how the ovaries work. It can lead to irregular periods, acne, extra hair growth and trouble with ovulation, which is the release of an egg each month. Research suggests PMOS affects around one in eight to one in ten women in the UK. This is one estimate from one population, not a fixed number for every woman.
The thyroid is a small gland in your neck. It makes hormones that control your metabolism, which is how your body turns food into energy. When the thyroid makes too much hormone, this is called hyperthyroidism, or an overactive thyroid. When it makes too little, this is called hypothyroidism, or an underactive thyroid. Hyperthyroidism affects around two in 100 people, and is up to ten times more common in women than in men.
Can You Have PMOS and a Thyroid Disorder at the Same Time?
You can have both PMOS and a thyroid disorder, such as hyperthyroidism, at the same time. Having one does not mean it caused the other. The two conditions can occur together, but current evidence does not show that either one causes the other.
This can feel confusing, since the two conditions show up together fairly often. The honest answer from current research is that they can exist side by side without one being the reason for the other. If you have been told you have PMOS, this does not mean a thyroid problem caused it. The same is true the other way round.
Shared Symptoms: Why PMOS and Thyroid Issues Can Look Alike
PMOS and thyroid disorders, including hypothyroidism and hyperthyroidism, can cause some of the very same symptoms. These include:
- Irregular or missed periods
- Weight changes that are hard to explain
- Fatigue
- Thinning hair
PMOS and thyroid conditions are both common hormonal conditions. They can also look alike from the outside. This makes it easy to assume you know which one you have, but symptoms alone cannot tell you that. Only tests can.
The Hormone Connection: Too Much vs Too Little
PMOS and an overactive thyroid, or hyperthyroidism, both involve the body making certain hormones in larger amounts than it needs. But they work through different glands and different pathways. In hyperthyroidism, the thyroid gland releases too much hormone. This can speed up your metabolism, and this can cause sudden weight loss, an irregular heartbeat, or shaky hands.
PMOS works differently. It is often linked to low levels of estrogen and progesterone, which are two key reproductive hormones, at certain points in the cycle. This can lead to irregular periods, missed periods and unpredictable ovulation. Both conditions can disrupt your cycle and your energy levels. But they do it through very different hormone pathways in the body.
Does Having PMOS Raise Your Risk of Thyroid Disorders?
Research suggests that people with PMOS are more likely to have a thyroid disorder. People with PMOS have a higher risk of developing both hypothyroidism and hyperthyroidism, though hyperthyroidism appears to be less common than hypothyroidism in this group. Hypothyroidism is commonly seen alongside PMOS, though the exact relationship between the two conditions is not fully understood yet.
In one study from 2015, researchers suggested that PMOS may be linked to thyroid dysfunction, particularly autoimmune thyroid disorders such as Graves' disease and Hashimoto's thyroiditis, where the body's immune system affects the thyroid. This is one study's finding, using cautious language, so it should be seen as an early lead rather than a settled fact. On the other side, there is no evidence that hypothyroidism raises the chance of developing PMOS.
If you have PMOS, this is a reason to ask your doctor about a thyroid check. It is not a reason to worry that you already have a thyroid problem.
Why Are Thyroid Disorders More Common in Women?
Thyroid disorders show up more often in women than in men, and this pattern holds in India too. In a study of women in India, thyroid disorder was more common among women from better-off households. This finding runs against the common assumption that thyroid problems mainly affect poorer communities.
The same study also found something unexpected about salt. In this study, women who used iodized salt were 1.14 times more likely to have a thyroid disorder than women who did not. This goes against the common belief that more iodized salt lowers thyroid disorder risk. It is one study's finding, not an established rule. It shows how much is still being learned about thyroid health in Indian women.
Telling PMOS and Thyroid Symptoms Apart: What Your Doctor Can Do
PMOS and thyroid disorders share so many symptoms. Fatigue, weight changes and irregular periods are common to both. Because of this, you cannot tell them apart just by how you feel. A doctor usually starts with your history: when your symptoms began, your cycle pattern, and any family history of thyroid problems.
From there, a physical exam and blood tests can check your thyroid hormone levels. These tests can also look for signs linked to PMOS, such as hormone imbalances picked up through blood work or an ultrasound. Doctors are still refining how best to tell the two conditions apart in every case, so try not to self-diagnose from symptoms alone. If you suspect either condition, an Online Doctor Consultation for Women is a good place to start getting properly checked.
How Often Should You Be Screened?
If you have PMOS, it is worth asking your doctor how often a thyroid check makes sense for you, since this can depend on your symptoms and history. There is no single fixed schedule that applies to every woman, so this is a conversation to have directly with your doctor rather than something to decide on your own.
Living With PMOS, Thyroid Issues, or Both
A doctor's care is central to managing PMOS, a thyroid disorder, or both together. Alongside medical care, everyday habits like regular meals, sleep, movement and stress management can support your symptoms and general wellbeing. If you are managing more than one hormonal condition, a programme like Multi-Condition Care looks at your whole picture alongside your doctor's guidance.
Low estrogen and progesterone linked to PMOS can already make cycles unpredictable. Keeping a simple period diary can help you and your doctor spot patterns over time. Watch for new or worsening symptoms, such as a sudden weight change, a racing heart, or ongoing fatigue. Bring these to your doctor rather than guessing which condition is behind them. Getting the right tests early makes it easier to get the right kind of support going forward. You can also learn more on the Hormonal Health for Women hub.