IVF/ICSI outcomes of euthyroid infertile women with TAI: does treating with aspirin plus prednisone matter?

Abstract Background Thyroid autoimmunity (TAI) has been associated with adverse pregnancy outcomes. To settle with fertility problem, prescribing aspirin combined with prednisone (P+A) to women positive for antithyroid antibodies (ATA) is frequent in clinical practice, but the real effect remains controversial. Methods A multicenter, retrospective study was conducted in three reproductive centers from 2017 to 2020. We recruited 494 euthyroid infertile women positive for anti-thyroperoxidase and/or thyroglobulin antibodies (TPOAb and TgAb, respectively) with thyroid stimulating hormone (TSH) levels ranging 0.35-4.0mIU/L who were undergoing their first in vitro fertilization and embryo transfer (IVF-ET) cycle. Ultimately, 346 women were included of which 150 women were treated with prednisone (10mg/d) and aspirin (100mg/d), while the remaining 196 women were untreated (control group). Treatment started on the day of embryo transfer and continued until clinical pregnancy was determined. Results Clinical pregnancy rate (CPR) was 57.5% vs. 63.5% in the control and treated groups (P=0.414) for first fresh embryo transfer cycles and 57.8% vs. 61.8% for frozen-thawed embryo transfer cycles (P=0.606). Additionally, the live birth rate (LBR) at the fresh embryo transfer was 49.6% vs. 47.3% in the control and treated groups (P=0.762). Logistic regression revealed that P+A did not improve CPR or miscarriage rates (MR). Furthermore, we observed that low free triiodothyronine (FT3) was associated with high MR. Conclusions Utilizing an adjuvant treatment of P+A after the embryo transfer may be unnecessary in euthyroid women with TAI undergoing their first IVF-ET, regardless of embryo type (fresh or frozen).