Department of Clinical and Experimental Medicine, University of Catania, Policlinico "G. Rodolico", Via Santa Sofia 78, 95123, Catania, Italy.
Endocrinology, Department of Clinical and Experimental Medicine, University of Messina, Policlinico Universitario di Messina, Padiglione H, 4th floor, Viale Gazzi, 98125, Messina, Italy.
Endocrine. 2017 Dec;58(3):397-407. doi: 10.1007/s12020-017-1303-8. Epub 2017 Apr 20.
Testis was considered unresponsive to thyroid hormone for a long time. However, like in animals, the presence of thyroid hormone receptors in different testicular cell types was demonstrated also in humans. Accordingly, thyrotoxicosis and hypothyroidism have remarkable effects on testicular function and more extensively on fertility.
Thyrotoxicosis and hypothyroidism are associated with changes affecting the endocrine, sexual, or reproductive functions. Particularly, compared with controls, hyperthyroid patients have higher serum SHBG and lower free and bioavailable testosterone concentrations, a higher rate of astheno-zoospermia, oligo-zoospermia, and terato-zoospermia, and a higher prevalence of sexual disturbances, such as premature ejaculation. In hypothyroid patients, hormonal changes are in the opposite direction compared with hyperthyroid patients. Thyroid hormone regulates a number of functions in the testis, such as proliferation and differentiations of non-germ cells, steroidogenesis, and sperm motility. Furthermore, thyroid hormone regulates testicular redox status. Consequently, thyroid hormone excess or deficiency can affect testicular function at different levels.
In view of the high prevalence of thyrotoxicosis and hypothyroidism, a considerable part of infertile patients may harbor overt or subclinical thyroid disease. Identification and management of thyrotoxicosis/hypothyroidism associated infertility needs the collaboration of andrologists, endocrinologists, gynecologists, and general practitioners.
长期以来，人们一直认为睾丸对甲状腺激素没有反应。然而，就像在动物中一样，也在人类的不同睾丸细胞类型中发现了甲状腺激素受体。因此，甲状腺功能亢进和甲状腺功能减退症对睾丸功能有显著影响，更广泛地对生育能力有影响。
甲状腺功能亢进和甲状腺功能减退症与影响内分泌、性或生殖功能的变化有关。特别是与对照组相比，甲状腺功能亢进症患者的血清 SHBG 较高，游离和生物可利用的睾酮浓度较低，弱精症、少精症和畸形精症的发生率较高，以及性障碍（如早泄）的患病率较高。在甲状腺功能减退症患者中，激素变化与甲状腺功能亢进症患者相反。甲状腺激素调节睾丸中的许多功能，如非生殖细胞的增殖和分化、类固醇生成和精子活力。此外，甲状腺激素调节睾丸的氧化还原状态。因此，甲状腺激素过多或不足会在不同层面影响睾丸功能。
鉴于甲状腺功能亢进症和甲状腺功能减退症的高患病率，相当一部分不孕患者可能患有显性或亚临床甲状腺疾病。甲状腺功能亢进/减退症相关不孕的识别和管理需要男科医生、内分泌科医生、妇科医生和全科医生的协作。
