Chapter 10 - Antithyroid antibodies and reproductive function

Abstract

Currently, there is sufficient evidence that the presence of antithyroid antibodies (ATA), even in patients with euthyroidism, could be an independent risk factor for a complicated pregnancy. However, the mechanisms of the pathogenic effects of ATA on the reproductive system remain unclear. The purpose of this chapter is to review the possible mechanisms of ATA on reproductive organs. Three main alleged mechanisms of ATA on pregnancy can be considered. The first possible explanation is that ATA can serve as an epiphenomenon of the general autoimmune state as a result of generalized dysfunction of T-cells. The second explanation is based on the finding that levothyroxine therapy can improve obstetric outcomes even in patients with normal serum TSH levels. Such finding suggests that ATA can disrupt thyroid function, especially in conditions of increased body demand, such as pregnancy. The last explanation is that ATA themselves may damage reproductive tissues, such as zona pellucida, endometrium, and placenta, due to cross-reactivity. Counter arguments for each hypothesis are also discussed. Finally, the modern approaches to the diagnosis and treatment of pregnant and seeking pregnant patients with euthyroidism with ATA are summarized.