Association between anti-Mullerian hormone and antithyroid antibodies detectability and positivity in women assisted at a fertility clinic.

Objective: To evaluate the association between antithyroid antibodies detectability and positivity and ovarian reserve. Additionally, we aimed to evaluate the correlation between TSH levels and parameters of ovarian reserve [anti-Mullerian (AMH) levels and antral follicle count (AFC)].

Methods: Subjects were women seeking assisted reproductive therapy and oocyte cryopreservation. AMH, AFC and antithyroid antibodies were determined. In a subgroup of patients, antithyroid antibodies were stratified into categories for the association analyses. The reference values were as follows: antithyroid peroxidase antibody (TPOAb): undetectable (<9 IU/mL), low detectable (9-21 IU/mL), high detectable (22-34 IU/mL), and positive (> 34 IU/mL); antithyroglobulin antibody (TgAb): undetectable (< 10 IU/mL), low detectable (10-60 IU/mL), high detectable (61-115 IU/ mL), and positive (>115 IU/mL). AMH levels < 1.1 ng/mL and/or AFC < 7 follicles were considered to indicate low ovarian reserve.

Results: A total of 453 patients were enrolled. 24.4% had at least one positive antithyroid antibody. Low detectable values for TPOAb and TgAb were found in 42.3% and 66.9%, respectively. TPOAb and TgAb levels were not statistically different between women with AMH < or ≥ 1.1 ng/mL; there was also no statistically significant difference between antithyroid antibodies levels and AFC < or ≥ 7 follicles. AMH levels did not show significant association with detectability nor positivity of the antithyroid antibodies. No statistically significant correlation was observed between AMH and TSH nor AFC and TSH.

Conclusions: Although the detectability of TPOAb has been associated with different outcomes, TPOAb and/or TgAb were not associated with ovarian reserve in our study.