The prolactin test is performed to evaluate the blood levels of the prolactin hormone, determining whether they are high or low. Prolactin levels are measured in the investigation of various health issues such as menstrual irregularities, infertility (ovulation problems), galactorrhea (nipple discharge), gynecomastia, decreased libido, bone density problems, thyroid hormone imbalances, and certain psychiatric conditions. Additionally, pregnancy and breastfeeding can affect prolactin levels. Furthermore, it may be requested as a supplementary examination in the diagnosis of pituitary gland disorders, head traumas, specific infections, and pituitary tumors.