Objectives To investigate the clinical features of primary amenorrhea for pituitary prolactinoma and to evaluate the effectiveness of surgical treatment. Methods Clinical data of five patients with primary amenorrhea caused by pituitary prolactinoma were analyzed retrospectively. The tumors were classified into two types (E: enclosed in sella turcica; I: invasive) according to their invasiveness determined by the CT or MRI examinations. Transcranial and transsphenoidal approaches were employed to resect the...