Fertility and Hypothyroidism
Becoming and staying pregnant can be difficult (and heartbreaking if the latter occurs). Oftentimes we don’t know exactly why miscarriage happens, but we do know about the involvement of the thyroid in some women. Recent studies have looked at the association between fertility and the thyroid gland and found that conditions like hypothyroidism and Hashimoto’s Thyroiditis are contributors to infertility.
Thyroid disorders may affect your period in the following ways:
- Long and/or irregular cycles
- Heavy periods
- Recurrent miscarriage
- Little to no cervical fluid
- PMS including dysmenorrhea
- Prolonged spotting
Hormones such as thyroid stimulating hormone (TSH) and thyroid hormones (T4 and T3) are important for menstrual regularity, egg development and implantation.
Hypothyroidism occurs when TSH levels are increased beyond their normal limits, when there is not enough T4 secretion, or when there isn’t enough conversion of T4 to T3. The latter means that you can have NORMAL TSH levels but T4 and T3 could be off.
Hypothyroidism signs and symptoms look like:
- Low metabolism, which can lead to weight gain
- Low basal body temperature
- Low pulse or blood pressure
- Dry and/or scaly skin
- Dry hair and/or hair loss
- Slowed reflexes
- Intolerance to cold
Hashimoto’s is essentially an autoimmune version of hypothyroidism. It occurs when the body doesn’t recognize the thyroid gland as its own and attacks it, leading to the production of thyroid antibodies such as anti-TPO and thyroglobulin.
Additionally, there is also a connection between Hashimoto’s and gluten sensitivity/celiac disease. So if you’ve been looking for a reason to limit your gluten intake, here it is!
TSH During Pregnancy
During pregnancy, having ideal levels of TSH and thyroid hormones is important because they are associated with increased gestation (time between conception and birth), hypertension, growth restrictions, premature delivery and fetal hypothyroidism. It’s clear that the thyroid should be monitored throughout pregnancy.
The American Thyroid Association recommends that TSH should be checked in all women experiencing infertility, and some groups indicate that TSH should be equal to or less than 2.5mIU/L to reduce miscarriage risk.
Here’s the thing though, usually only TSH will be tested but this isn’t good enough! It’s important to understand everything that’s going on with the thyroid so ask for a comprehensive workup that looks like:
Thyroid and IVF
IVF can be a stressor to the thyroid. And although no studies have showed that treating hypothyroidism leads to an increase of live births, one study has shown that hypothyroid women have less of a response to ovarian stimulation and a lower rate of embryo transfer.
With infertility being so common nowadays, it’s important to take a good look at the thyroid – especially if you have a family history of thyroid disorders or experiencing any of the above signs or symptoms.
Treating thyroid conditions does not just require medication, particular nutrients like selenium or Vitamin D can also be helpful, as well as trying out some dietary changes if you happen to have high antibody levels. Speak to your naturopathic doctor to see how they can complement your treatment plan.
Busnelli, A., Somigliana, E., Benaglia, L., Leonardi, M., Ragni, G. and Fedele, L. (2013). In Vitro Fertilization Outcomes in Treated Hypothyroidism. Thyroid, 23(10), pp.1319-1325.
Biondi, B., Cappola, A. and Cooper, D. (2019). Subclinical Hypothyroidism. JAMA, 322(2), p.153.
Maraka, S., Singh Ospina, N., Mastorakos, G. and O’Keeffe, D. (2018). Subclinical Hypothyroidism in Women Planning Conception and During Pregnancy: Who Should Be Treated and How?. Journal of the Endocrine Society, 2(6), pp.533-546.
Green, K., Werner, M., Franasiak, J., Juneau, C., Hong, K. and Scott, R. (2015). Investigating the optimal preconception TSH range for patients undergoing IVF when controlling for embryo quality. Journal of Assisted Reproduction and Genetics, 32(10), pp.1469-1476.
Orouji Jokar, T., Fourman, L., Lee, H., Mentzinger, K. and Fazeli, P. (2017). Higher TSH Levels Within the Normal Range Are Associated With Unexplained Infertility. The Journal of Clinical Endocrinology & Metabolism, 103(2), pp.632-639.