Hyperprolactinaemia

Abstract

Hyperprolactinaemia is the most common hormonal abnormality affecting the pituitary gland. The most frequently seen non-physiological causes include drug-induced hyperprolactinaemia, polycystic ovarian syndrome, and benign prolactin-secreting tumours of the anterior pituitary gland (prolactinomas). Tumours may be classified as either micro- (<1 cm in diameter), which are most common, or macroprolactinomas (>1 cm in diameter). Prolactinomas most commonly occur in women between 30 and 50 years of age and hyperprolactinaemia usually presents with galactorrhoea or symptoms of disturbed gonadal function (secondary amenorrhoea, anovulation, and infertility in women; erectile dysfunction, reduced shaving frequency in men). Macroprolactinomas may also present with local pressure effects (headache, visual fi eld loss). Dopamine agonists, such as bromocriptine and cabergoline, are the first-line treatment for both micro- and macroprolactinomas. Nowadays, surgical treatment is rarely required even for macroprolactinomas. The main aim of treatment is resolution of symptoms, and, therefore, restoration of gonadal function. For patients with microprolactinomas, dopamine agonist treatment should be withdrawn for a trial period after two to three years, as in around one-third of cases the prolactin level will return to normal. In women with microprolactinomas who become pregnant, dopamine agonists should be discontinued once pregnancy is confirmed. For women with macroprolactinomas, bromocriptine can be continued throughout the pregnancy.