In the human female, the urethra is about 1.5–2 inches (4–5 cm) long and exits the body between the clitoris and the vagina, extending from the internal to the external urethral orifice. It is placed behind the symphysis pubis, embedded in the anterior wall of the vagina, and its direction is obliquely downward and forward; it is slightly curved with the concavity directed forward. Its lining is composed of stratified squamous epithelium, which becomes transitional near the bladder
The urethra consists of three coats: muscular, erectile, and mucous, the muscular layer being a continuation of that of the bladder. Between the superior and inferior fascia of the urogenital diaphragm, the female urethra is surrounded by the Sphincter urethrae (urethral sphincter). Somatic (conscious) innervation of the external urethral sphincter is supplied by the pudendal nerve. The uro-genital sinus may be divided into three component parts. The first of these is the cranial portion which is continuous with the allantois and forms the bladder proper.
The pelvic part of the sinus forms the prostatic urethra and epithelium as well as the membranous urethra and bulbo urethral glands in the male and the membranous urethra and part of the vagina in females. The area above and on both sides of the female urethra is thought by some to be sexually sensitive and is sometimes referred to as the U-spot or urethral erogenous zone.