Hormones are incredibly important during the fertility stages, however often the thyroid hormones are neglected over the reproductive hormones, such as oestrogen. Your thyroid is a butterfly shaped gland located at the front of your neck that produces hormones to regulate your metabolism and other vital functions of the body such as your body’s ability to conceive and bring a baby to full term.

Thyroid health
In terms of thyroid health, there is a spectrum of results that can cause the thyroid gland to be dysregulated resulting in the overproduction (hyperthyroidism) or underproduction (hypothyroidism) of thyroid hormones.

The most common cause of hypothyroidism is the autoimmune condition, Hashimoto’s thyroiditis. Graves’ disease is the autoimmune condition which is the most common cause of hyperthyroidism.

How does thyroid disorders disrupt fertility?
Both hyperthyroidism and hypothyroidism can each negatively affect your chances to conceive and hold a baby to full term. TSH, your Thyroid Stimulating Hormone levels can affect ovulation and will affect subsequently affect the luteal phase of the reproductive cycle.


Hypothyroidism and Fertility
Too little thyroid hormone can impact fertility in the following ways:

  • Disruption of the menstrual cycle, making it harder to conceive.
  • Interference with the release of an egg from the ovaries (ovulation)
  • Increased risk of miscarriage
  • Increased risk of premature birth
    Hypothyroidism is common in women and can be detected via a blood test of your
    total thyroid panel (more on this below). However, many women still remain
    undiagnosed, especially if your thyroid lies within the sub-clinical ranges.
    Symptoms of hypothyroidism include:
  • Inability to lose weight
  • Fatigue
  • Dry hair and skin
  • Intolerance to cold
  • Frequent and heavy menstrual cycles
  • Changes in mood
    Naturopathy offers many ways to support the thyroid especially if underactive, via
    herbs and nutritional supplements, as well as diet amendments.
    Hyperthyroidism and Fertility
    Too much thyroid hormone caused by hyperthyroidism can affect fertility by:
  • Disrupting the menstrual cycle
  • Causing a reduction in sperm count
  • Increasing the risk of early-term miscarriage
  • Increasing the risk for premature birth
    Symptoms of an overactive thyroid include:
  • Mood changes and anxiety
  • Inability to gain or maintain weight
  • Oily skin and hair
  • Heart palpitations

Autoimmune disease and fertility
The two main causes for thyroid disruption include autoimmune conditions. Autoimmune diseases cause an increase in inflammation throughout the body as the immune system is responding to signals that the cells of your own body need to be destroyed.

It is very important to stabilise your thyroid hormones as well as your antibodies to increase your chances of conceiving and also during pregnancy.

Where should my thyroid levels be to look at fertility?
Ideally, it is important to check all of your thyroid hormones levels; not just TSH.
The optimal thyroid hormones for conception:
TSH - between 1-1.5 mU/L
T4 - between 15 and 16pmol/L
T3 - between 5-6 pmol/L

Thyroid antibodies such as TRAB and TPO should be low as possible (<20 IU/mL).

What to do if you are not sure about the health of your thyroid?
If you are suffering from some of the symptoms mentioned, or not sure if your thyroid is working optimally or you have been struggling to conceive and want to deep dive into the health of your thyroid, book a consult with Nat our naturopath to work on optimising your thyroid function.