Thyroid & Women’s Health: Through All Stages

Written By Kirsty Matijevic

Your thyroid may be small, but it plays a big role in your health — particularly when it comes to women’s health, fertility, pregnancy and postpartum wellbeing. Women are more prone to thyroid concerns than men, including underactive thyroid function, thyroid nodules and autoimmune thyroid conditions such as Hashimoto’s and Graves’ disease.

So, why are women more vulnerable?

Why are thyroid problems more common in women?

Hormones play a role

Your hormones don't work independently. They constantly influence one another, and oestrogen and progesterone have a close relationship with thyroid hormones. This may help explain why thyroid problems can become more noticeable during times of major hormonal change, including:

  • Puberty

  • Pregnancy

  • Postpartum

  • Perimenopause

  • Menopause

Your thyroid and fertility

Thyroid health is closely connected with reproductive health. An underactive thyroid can affect ovulation and menstrual cycles, including contributing to heavier or less frequent periods. Even when thyroid hormone levels appear relatively normal, some women can experience symptoms or have underlying thyroid issues that aren't obvious from TSH alone.

Pregnancy puts extra demands on your thyroid

Pregnancy is a time of significant change for your thyroid. Your thyroid needs to produce more hormones to support both mum and baby, while nutritional demands also increase. This means pregnancy can place considerable pressure on your thyroid — particularly if nutritional stores were already low.

Thyroid dysfunction is estimated to affect around 2–3% of women during pregnancy, although symptoms often are overlooked because fatigue, low mood and changes in energy are often considered a normal part of pregnancy.

Your thyroid is particularly important during early pregnancy. Your baby's thyroid isn't fully developed during the early stages of pregnancy, so maternal thyroid hormones play an important role in supporting baby's development. Pregnancy also changes iodine, selenium and other thyroid-relevant nutrient requirements, thyroid hormone production and the way thyroid hormones are transported and used.

If you have a history of thyroid disease, thyroid antibodies or fertility difficulties, it's worth discussing thyroid testing and monitoring with your healthcare team before and during pregnancy.

And then comes postpartum...

After birth, reproductive hormones shift dramatically again. At the same time, your body is recovering from pregnancy and birth, and breastfeeding can place ongoing nutritional demands on mum. This combination of hormonal change, increased nutrient demands and postpartum depletion can make thyroid health particularly important during this stage. Postpartum thyroiditis can also develop, and thyroid symptoms may sometimes be mistaken for simply being a "tired new mum."

And don't forget perimenopause

Pregnancy isn't the only major hormonal transition that can affect thyroid health. During perimenopause and menopause, oestrogen and progesterone change significantly, which can influence thyroid function and make existing symptoms more noticeable.

This is another stage of life where symptoms such as fatigue, changes in weight, mood changes and temperature sensitivity can sometimes overlap with both thyroid and hormonal changes.

TSH isn't the whole picture

TSH may be the commonly tested marker for thyroid function, but it does not tell us everything about what is actually happening with your thyroid. In fact, it can miss quite a significant amount of the picture. This is why testing TSH alone often leads to many women with thyroid issues feeling lost, unsure or even dismissed about their thyroid health concerns and symptoms, especially is TSH comes back ‘normal’.

Depending on your symptoms and history, it can also be useful to look at:

  • T3 and T4

  • Reverse T3

  • Thyroid antibodies

  • Nutritional status

  • Menstrual and fertility history

Looking at the bigger picture can provide a much better understanding of what may be going on.

What about thyroid antibodies?

Hashimoto's and Graves' disease are autoimmune thyroid conditions, meaning the immune system targets the thyroid. The main thyroid antibodies we look at are TPO antibodies and thyroglobulin antibodies (TgAb). Importantly, antibodies can sometimes be present before obvious changes in thyroid hormone levels. This makes them particularly relevant when investigating thyroid symptoms, fertility concerns or pregnancy history.

Supporting your thyroid naturally

A thyroid diagnosis doesn't mean you're powerless. While there isn't always one obvious cause, there are plenty of areas we can explore to support thyroid health and overall wellbeing.

This may include:

Nourishing your body

Focus on a varied, nutrient-dense whole-food diet with quality protein, vegetables, fruit, whole-food carbohydrates and healthy fats.

Checking nutritional status

Thyroid hormone production and metabolism rely on a range of nutrients, so nutritional deficiencies are worth identifying and addressing where appropriate.

Supporting gut and immune health

For women with autoimmune thyroid conditions, looking at gut health, inflammation, food triggers, stress and lifestyle can form part of a broader approach.

Prioritising sleep and stress management

Your body has a lot to manage during hormonal transitions. Supporting sleep, recovery and stress levels is an important part of the bigger picture.

The bottom line

Your thyroid doesn't exist in isolation.

It interacts with your reproductive hormones, nutritional status, immune system and overall health — and these relationships can become particularly important during fertility, pregnancy, postpartum and menopause.

If you're struggling with fatigue, hormonal symptoms, fertility, pregnancy or postpartum recovery, your thyroid may be one piece of the puzzle worth exploring.

You don't have to simply put up with feeling unwell. Understanding what's happening in your body is the first step towards feeling more in control of your health.

Ready to understand your health better?

At Nest & Nourish Naturopathy, I take a personalised approach to women's health — looking at the bigger picture rather than focusing on symptoms in isolation. Because you deserve clear answers, individualised care and support that actually makes a difference.

If you're experiencing thyroid, fertility, pregnancy or postpartum concerns, book an appointment today and let’s work together to help you feel more like yourself again.

This information is for educational purposes only and is not intended to replace individual medical advice, diagnosis or treatment. If you have concerns about your thyroid, fertility or pregnancy, speak with your appropriate healthcare practitioner.

Kirsty Matijevic