An abnormally elevated serum prolactin, >1.14 nmol/L in clinical practice, is called hyperprolactinemia. In fact, the most common cause is pituitary disease, most often pituitary microadenoma, and the clinical features of the disease are overflow of milk and menstrual disorders, often with a range of symptoms such as prolonged amenorrhea, infertility, and headache. The most common diagnosis is a cranial MRI to clarify the presence of pituitary microadenoma, and after diagnosis, the cause should be promptly identified and treated. Current treatments include pharmacologic, surgical, and radiotherapy. Bromocriptine is currently the first-line drug commonly used to treat pituitary microadenomas. The earliest symptom that a patient with elevated prolactin may present to the obstetrics and gynecology department is amenorrhea. Patients may present with prolonged absence of menstruation or infertility, and abnormally elevated prolactin or breast overflow may be found during blood tests. In this case, the first step is to rule out the presence of pituitary microadenoma. After the presence of pituitary microadenoma is clarified by cranial MRI, pharmacological treatment can be considered, with the first line of treatment being bromocriptine for at least 1 cycle of 3 months.