The term “polycystic” refers to the presence of multiple fluid-filled sacs (cysts) within each ovary.
These cysts are actually ovarian follicles that are unable to mature enough to release egg cells.
In PCOS, the follicles cannot grow and mature properly due to high androgen levels.

Illustration by Emily Roberts, Verywell
With hypothyroidism, the main hormone change is the decreased amount of thyroid hormone.
Especially when there is another condition (hyperprolactinemia) that is due to high prolactin.
These hormones work to regulate your menstrual cycle.
In people with PCOS, the LH-FSH ratio is higher than in those without PCOS.
Likewise, research has found that the LH-FSH ratio is higher in people with Hashimoto’s thyroiditis.
Weight and PCOS
Thyroid-stimulating hormone (TSH) is higher in people who are considered overweight.
Likewise, those with PCOS are more likely to be overweight.
Similarly, research has found that women with PCOS have more hypoechogenic thyroids when compared to those without PCOS.
There is some data to suggest that women with PCOS are more vulnerable to developing autoimmune diseases.
2013 Jan;21(1):101-6.
Danfeng D, Xuelian L.The relationship between thyroiditis and polycystic ovary syndrome: a meta-analysis.Int J Clin Exp Med.
2013;6(10):880-9.
2015 Jan-Feb; 19(1):25-9. doi: 10.4103/2230-8210.146860