Thyrotropin receptor autoantibodies and early miscarriages in patients with Hashimoto thyroiditis: a case–control study

Abstract

We have previously hypothesized that early miscarriage in women with Hashimoto thyroiditis might be the result of a cross-reactivity process, in which blocking autoantibodies against thyrotropin receptor (TSHr-Ab) antagonize hCG action on its receptor on the corpus luteum. To test this hypothesis from the clinical perspective, we investigated the presence of TSHr-Ab in Hashimoto thyroiditis patients with apparently unexplained, first-trimester recurrent miscarriages compared to that in Hashimoto thyroiditis patients with documented normal fertility. A total of 86 subjects (43 cases and 43 age-matched controls) were finally included in a case–control study. No difference in the prevalence of TSHr-Ab positivity was detected between cases and controls (Fisher’s exact test, p value = 1.00). In patients with recurrent miscarriages, TSHr-Ab concentrations did not predict the number of miscarriages (univariate linear regression, p value = 0.08). These results were robust in sensitivity analyses, including only cases with full investigation or those with three or more miscarriages. We conclude that no role could be advocated for TSHr-Ab in the aetiology of recurrent miscarriages in women with Hashimoto thyroiditis.

• Autoantibodies
• Hashimoto thyroiditis
• miscarriages
• pregnancy outcomes
• thyroid autoimmunity
• thyrotropin

Acknowledgements

We are thankful to Nikolaos Karyotis (BSc, First Department of Internal Medicine, AUTH, and Immunotherapy Centre of N. Greece), Anna Maladaki (MD, First Department of Internal Medicine, AUTH), Anna Mitsoli, BSc (First Department of Obstetrics and Gynecology, AUTH) and Diamantis Katsaros (technician, First Department of Internal Medicine, AUTH) for their help in the conduct of the study.