Urethra Overview
©1996-1998 University of Kansas Medical Center
Department of Anatomy and Cell Biology
The urethra is a fibromuscular tube which conveys urine from the bladder to the exterior. It differs in structure and function in males and females. In the male, the tube is about 20 cm. in length and also transports seminal fluid during ejaculation. The female urethra is much shorter, about 4 cm. Histological structure also differs between male and female urethrae.
The epithelial lining of the female urethra changes from transitional epithelium at the bladder end to non-keratinizing stratified squamous epithelium distally.
The epithelial lining of the male urethra changes from transitional epithelium at the bladder end to pseudostratified epithelium through prostatic, membranous and most of penile urethra, eventually changing to nonkeratinizing stratified squamous epithelium distally.
The lamina propria of both male and female urethra are vascular, but the male is much more vascular with its extensive corpus spongiosum.