Levels of TSH receptor antibodies (TRAb IgG) are raised in women with endometriosis, suggests a new study published online Sept. 16, 2022 in the European Journal of Obstetrics & Gynecology and Reproductive Biology.¹

Swedish researchers examined the role of TRAb IgG as a likely marker for  endometriosis in a cross-sectional study in women with a confirmed diagnosis of endometriosis. Two control groups were also included in the trial; one with 50 healthy blood donors and the other comprising 114 women from Malmö Offspring Study.

Out of the 172 women with endometriosis in the study, 29% had TRAb IgG levels greater than the current cut-off of 1.0 IE/L, whereas just 2.6% among the 114 women from the Malmö Offspring Study had TRAb IgG above 1.0 IE/L. When the earlier limits of ≥0.3 IE/L were considered, 94.5% had TRAb levels greater than 0.3 IE/L compared to 7.9% of the controls. Both TRAb IgG and IgM levels were elevated in women with endometriosis versus both control groups. Compared to the control group comprising of healthy blood donors, the endometriosis group did not exhibit antibodies against follicle stimulating hormone (FSH), FSH receptor (FSHR), human chorionic gonadotropin (hCG), luteinizing hormone (LH), LH receptor (LHR) or TSH.

The study observed no cross-reactivity of raised TRAb levels with other autoantibodies. No correlation with age, disease duration, AXIN1, TSH, thyroid hormones or gastrointestinal symptoms was noted either. These findings suggest that high levels of TSH receptor antibodies may be indicative of a possible diagnosis of endometriosis. Therefore, such women should be investigated for endometriosis.

Reference

1. Svensson A, et al. TSH receptor antibodies (TRAb) – a potential new biomarker for endometriosis. Eur J Obstet Gynecol Reprod Biol. 2022 Sept.16; DOI:https://doi.org/10.1016/j.ejogrb.2022.09.013.