The bladder is not considered retroperitoneal. It is classified as a pelvic organ and is located within the pelvis, anterior to the uterus in females and to the rectum in males. The term ‘retroperitoneal’ refers to organs that are situated behind the peritoneum, which is the membrane lining the abdominal cavity.
While some organs such as the kidneys and adrenal glands are retroperitoneal, the bladder is not included in this category because it is fully surrounded by peritoneum and not located behind it. Its positioning allows for the flexibility and expansion needed to store urine.