Objective: To investigate the incidence of thyroid dysfunction, thyroid antibodies, and the correlation with semen and hormonal parameters in infertile men.
Design: Prospective study.
Setting: University-based andrology laboratory.
Patient(s): Three hundred five infertile men with idiopathic infertility.
Intervention(s): Medical history, clinical examination, semen analysis, measurement of free thyroxin (fT4), free triiodothyronine (fT3), basal thyroid-stimulating hormone (bTSH), LH, FSH, T, free testosterone (fT), PRL, E2, sex hormone-binding globulin (SHBG), DHEAS, and the thyroid antibodies thyreoglobulin antibody (TGA), thyroid peroxidase antibody (TPO-Ab), and thyroid receptor antibody (TRAK).
Main outcome measure(s): Incidence of thyroid dysfunction and thyroid antibodies, as well as the correlation with hormones and the results of semen analyses.
Result(s): No manifest thyroid dysfunction was observed. Latent thyroid dysfunction and latent hypothyroidism were diagnosed in 11.5% and 3% of infertile men, respectively. No correlation between thyroid dysfunction and semen parameters was detected. bTSH correlated significantly with PRL (P<.001). Thyroid antibodies were elevated in 7.5%. Elevated TPO-Ab were significantly correlated with pathozoospermia (P=.036) and asthenozoospermia (P=.049).
Conclusion(s): Latent thyroid dysfunction had no impact on semen parameters. In patients with elevated TPO-Ab levels, pathozoospermia or asthenozoospermia should be considered.