The Bottom Line This study showed prevalence of hyperprolactinemia in subclinical hypothyroidism is notable and this disorder is more common in female subclinical
hypothyroidism than the men.
Bahar, Adele, et al. “Hyperprolactinemia in association with subclinical hypothyroidism.” Caspian journal of internal medicine 2.2 (2011):229-33. http://tinyurl.com/hhgjqmx
Hyperprolactinemia is the most prevalent endocrine disorder in hypothalamicpituitary axis. Pathologic hyperprolactinemia is generally applied for the situation in which prolactin level increases because of some reasons other than physiologic causes. Prolactin secretion is controlled by prolactin inhibitor factor that is secreted from hypothalamus, other factors like vaso active inhibitory peptide and Thyroid releasing hormone cause to increase prolactin secretion. In fact, TRH in addition to increasing TSH causes to rise prolactin level . In patients with primary hypothyroidism, increased levels of TRH can cause to rise prolactin levels and these patients may have galactorrhea. Different increased level of serum prolactin has been reported in 30% of patients with primary hypothyroidism. Subclinical hypothyroidism is defined by high TSH and normal thyroid hormones.