The thyroid gland is a small butterfly-shaped organ located in the neck that releases thyroid hormones. These hormones not only have a key role in metabolism, but also a very crucial role in our reproductive health, right from the development of eggs to implantation, placentation, continuation of the pregnancy, as well as adequate foetal growth and development.
For many women, silent thyroid disorders tend to go unnoticed, only to present as infertility or miscarriages. So, how do these thyroid disorders cause infertility?
With the increase in chronic stress and endocrine disruptor chemicals, thyroid disorders, both immune-related and non-immune-related, have increased in recent years which can contribute to conception-related difficulties as well as miscarriages.
Thyroid imbalance, fertility issues and miscarriages: What’s the link?
When thyroid hormone production is low, the pituitary gland in the brain releases more thyroid-stimulating hormone, or TSH. In response to this rise in TSH, there is a concurrent increase in prolactin. High Prolactin, on the other hand, interferes with the menstrual cycles, making them irregular leading to defective egg development and ovulation.
Low thyroid levels can also alter SHBG, or sex hormone-binding globulin, which is responsible for binding the oestrogen and progesterone hormones. These hormones play a vital role in egg production and endometrial development which fail to happen properly. This becomes even more important in IVF cycles, where external oestrogen and progesterone can interfere with TSH levels and hence need stringent monitoring of these laboratory values.
When thyroid production is high, menstrual abnormalities are quite common. Hyperthyroidism could be autoimmune in nature in around 15 per cent of cases wherein antibodies could be present against developing eggs and embryos as well, creating a hostile environment within the uterus. This can lead to implantation failure and recurrent miscarriages.
Why do working women miss recognising thyroid disorders?
Thyroid disorders often remain undiagnosed in working women mostly because of a lack of awareness. There is also a common myth surrounding thyroid disorders that once a person’s thyroid levels return to normal after taking medication, they no longer need to continue it. It’s important to understand that the deficiency in thyroid hormone levels was fulfilled by the supplemented medication. Hence, the normal value. So, it’s important to consult your doctor before altering thyroid medications.
Pre-pregnancy thyroid screening:
In clinical practice, thyroid screening is an important consideration before pregnancy and abnormal thyroid levels have to be optimised repeatedly throughout the periconceptional period and pregnancy. Many times, such screening can help pick up subclinical hypothyroidism, which could be strictly monitored, thus preventing further complications.
How can you support reproductive health?
Certain lifestyle changes are necessary to maintain reproductive health. Adequate sleep and proper stress management are of utmost importance and can make a big difference to not only your reproductive health, but also your overall general health. Regular exercise and healthy calorie intake, avoidance of cruciferous vegetables in very large amounts, avoidance of smoking and paying attention to gut health can improve thyroid-related reproductive decline.
(The author is a Consultant - IVF & Reproductive Medicine, Manipal Hospital Whitefield and Varthur)
The opinions expressed in this article are those of the author and do not purport to reflect the opinions or views of THE WEEK.
