Preliminary analyses of the samples provide no indication for a clinically relevant relationship between hyperprolactinemia and stimulation of adrenal steroidogenesis.

The purpose of this study is to explore the effects of prolactin on adrenal steroid profiles in patients with hyperprolactinemia due to prolactinomas before and after initialisation of treatment.

Prolactin is known to influence many biological processes. One potential target is the adrenal gland, where prolactin may stimulate the production of adrenal steroid hormones. Conditions of increased prolactin production(hyperprolactinemia) could, therefore, increase concentrations of adrenal steroids. One of the potential implications would be false doping accusations of athletes engaging in elite sports.

This interaction between prolactin and adrenal steroidogenesis, however, remains poorly understood, and the available research findings are conflicting.

The investigators, therefore, seek to explore the relationship between prolactin and adrenal steroidogenesis by monitoring prolactin levels and blood and urinary steroid profiles of patients with hyperprolactinemia due to prolactinomas before and after treatment initialisation.

Inclusion Criteria:

• Aged 18 years or older
• Female and pre-menopausal
• Serum prolactin > 150 ng/ml

Exclusion Criteria:

• Corticotropic and/or thyreotropic insufficiency
• Pregnancy, planned pregnancy or breastfeeding
• Physical or psychological condition likely to interfere with the normal conduct of the study and interpretation of the study results as judged by the investigator
• Incapacity to give informed consent

The study will involve up to 17 pre-menopausal female individuals with hyperprolactinemia due to prolactinomas, who will undergo treatment at the University Hospital Bern.