What is the Urethra

The Urethra is a tube connected to the bladder. Urine is held in the bladder until it becomes full and then it travels through the urethral opening to be released from the body. Its anatomy is different in men and women. One of the most common differences is that men have longer urethras than do women. Possible urethral problems can include pain, infections, and cancer.

Generally, all humans have urethras. In men, the urethra is part of the reproductive system. Located in the penis, it transports urine and semen from the body. The urethral tube in males typically measures about 8 inches (about 20.3 cm) long.

In women, the urethra generally is about 1.5 inches (about 3.8 cm) long. Unlike males, it is not part of the female reproductive system. Instead, it is located above the opening of the vagina, within the labia minora. Its only purpose in women is to serve as an exit site for urine.

Anatomy of the Urethra

Histological features

The epithelium of the urethra starts off as transitional cells as it exits the bladder. Further along the urethra there are stratified columnar cells, then stratified squamous cells near the external urethral orifice.
There are small mucus-secreting urethral glands, that help protect the epithelium from the corrosive urine.

Length of the urethrae

Male urethra

In the human male, the urethra is about 8 inches (20 cm) long and opens at the end of the penis. The urethra provides an exit for urine as well as semen during ejaculation.
The urethra is divided into four parts in men, named after the location:

Region Description Epithelium
pre-prostatic urethra This is the intramural part of the urethra and varies between 0.5 and 1.5 cm in length depending on the fullness of the bladder.

Female urethra

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

Urethral Disorders

The urethra is the tube that allows urine to pass outside the body. In men, the urethra is a long tube that runs through the penis. In women, the urethra is short. Urethral problems may happen due to aging, illness or injury. They include:
  • Urethral stricture: a narrowing of the opening of the urethra
  • Urethritis: inflammation of the urethra, sometimes caused by infection

Medical problems of the urethra

The medical problems of the Urethra include:
  • Hypospadias and epispadias are forms of abnormal development of the urethra in the male, where the meatus is not located at the distal end of the penis (it occurs lower than normal with hypospadias, and higher with epispadias). In a severe chordee, the urethra can develop between the penis and the scrotum.
  • Infection of the urethra is urethritis, said to be more common in females than males. Urethritis is a common cause of dysuria (pain when urinating).
  • Related to urethritis is so called urethral syndrome
  • Passage of kidney stones through the urethra can be painful, which can lead to urethral strictures.
  • Cancer of the urethra.
  • Foreign bodies in the urethra are uncommon, but there have been medical case reports of self-inflicted injuries, a result of insertion of foreign bodies into the urethra such as an electrical wire