Live-birth rate in euthyroid women with recurrent miscarriage and thyroid peroxidase antibodies

Thyroid autoimmunity with normal thyroid function is associated with recurrent miscarriage (RM), but the association with live birth is less clear. Therefore, we determined the association between thyroid peroxidase antibodies (TPO-Ab) and live-birth rate (LBR) in a retrospective cohort of euthyroid women with unexplained RM. We included 202 women of which 28 were TPO-Ab positive (13.9%) and 174 were TPO-Ab negative. TPO-Ab positive women (n = 10) without levothyroxine treatment had a lower LBR (29%) compared to TPO-Ab negative women (51%) (HR 0.23, 0.07-0.72, p = 0.012). The LBR in women with TPO-Ab receiving levothyroxine was not different compared women without TPO-Ab (60% versus 51%, p = 0.50). In conclusion, TPO-Ab are associated with a lower LBR in euthyroid women with unexplained RM and these women may benefit from treatment with levothyroxine.