Ovarian stimulation does not induce thyrotropin receptor autoantibodies in women with thyroid autoimmunity

Women of subfertile couples with thyroid autoimmunity (TAI) have an increased risk of miscarriage when pregnant after an assisted reproductive technology (ART) treatment. This might amongst others be due to the presence of thyrotropin receptor antibodies (TSH-R-Ab) that can impede the development of the corpus luteum. TSH-R-Ab can be present in women with TAI and/or be induced by the ovarian stimulation procedure (OS) that is performed to initiate the ART. In this prospective pilot study, we determined the presence of both binding and functional TSH-R-Ab (stimulating or blocking) with five different assays before and after OS in ten women (eleven cycles) with TAI of subfertile couples and in one woman without TAI. Mean (SD) age was 38.8 (±3.2) years, median (range) cumulative OS dose 1413 (613-2925) IU/L. Median baseline serum levels of thyrotropin, free thyroxine, and thyro-peroxidase antibodies were 2.33 (2.23-2.61) mIU/L, 16.8 (14.4-18.5) pmol/L and 152 (86-326) kIU/L, respectively. Oestradiol levels increased during OS from 40 (26-56) ng/L to 963 (383-5095) ng/L; P < .01. TSH-R-Ab measurements in all subject samples were below the cut-off of the corresponding immunoassay and four bioassays before or after OS.