3 Fat Chicks on a Diet Weight Loss Community - Link Between Hashimoto's Disease (Thyroiditis) and PCOS

A medical study was recently published that showed a relationship between PCOS and Hashimoto's Disease, which is autoimmune thyroiditis. Autoimmune thyroiditis is an inflammatory condition where your immune system attacks and damages your thyroid gland. As we said in our April newsletter, the thyroid is important for reproductive health.

The purpose of this multicenter study was to investigate the prevalence of autoimmune thyroiditis in women with polycystic ovary syndrome (PCOS). There were 175 women with PCOS and 168 women who did not have PCOS in the study. All of the women had extensive lab work.

The PCOS patients were characterized by an increased LH/FSH ratio, low progesterone, elevated testosterone and a high prevalence of hirsutism, but no differences in estrogen levels were found. In addition, 27% of the PCOS women had elevated thyroid-specific antibodies as compared to only 8.3% of the normal women. Elevated antibodies suggest an aroused immune system that is causing inflammation.

Thyroid ultrasound showed that 42.3% of PCOS women, but only 6.5% of the controls, had thyroid tissue images typical of autoimmune thyroiditis (Hashimoto's Disease). The PCOS women also had higher levels of TSH (thyroid stimulating hormone) than the non-PCOS women, suggesting that the PCOS thyroid is not as successful in making enough thyroid hormone.

The importance of the thyroid hormone for the adequate functioning of multiple organ systems within the body cannot be overstated. The production of adequate quantities of thyroid hormones is necessary for normal fetal and neonatal growth and development, as well as proper functioning of adult organ systems, cardiovascular system, lipid and carbohydrate metabolism, and the neuromuscular and skeletal systems.

A major ffect of abnormal thyroid levels is changes in ovulation and menstruation. Ovulation may be impaired by changes in the production of: sex hormone binding globulin (SHBG), follicle stimulating hormone (FSH), estrogen, and androgens. The body compensates by altering the production of thyroid releasing hormone (TRH). The changes in TRH will affect the feedback loop between the hypothalamus, pituitary, and the ovary, leading to changes in ovulation and menstruation. Early stages of thyroid dysfunction (before symptoms are obvious) can lead to subtle changes in ovulation and endometrial receptivity, which then may have profound effects on fertility.

Bottom Line: This study suggests that 4 of every 10 PCOS women probably have impaired thyroid function, due to autoimmune thyroiditis (Hashimoto's Disease). Therefore, an important component of your PCOS treatment is to get a thorough thyroid evaluation from your doctor. As we've said before, just taking birth control pills is not the answer to PCOS.

Sources:
Janssen, OE et al, High prevalence of autoimmune thyroiditis in patients with polycystic ovary syndrome, Eur J Endocrinol. 2004 Mar;150(3):363-9