Thyroid cysts refer to sac-like formations within the thyroid gland that contain fluid, typically benign with rare cases of malignancy. The fluid inside these cysts, also known as blisters, has no secretory function and does not affect thyroid function, making it possible to become pregnant with a thyroid cyst. However, it is important to note that during pregnancy, if the cyst rapidly enlarges or if there is localized pain, it could be due to bleeding inside the cyst which requires urgent treatment. Aspiration of the cyst fluid can be done through fine needle aspiration to relieve pressure, and ethanol ablation can be used to close the cyst cavity. This minor surgery is generally tolerable and does not affect pregnancy.