Duplication of urethra is a very rare condition where there is an extra urethra, instead of the normal one. Urethral duplications can be classified into three types: incomplete urethral duplication (type 1), complete urethral duplication (type 2), and urethral duplication as a result of two bladders. The urethra is the tube that connects the urinary bladder to the genitals for the removal of fluids from the body. In men, the urethra is a long tube that runs through the penis. In women, the urethra is shorter and emerges above the vaginal opening.

There are 3 different types of duplication of urethra. In type 1, the extra urethra arises from the primary urethra and may or may not extend to the external genitals. In type 2, the extra urethra either arises from another opening in the bladder or connects with the primary ureter at the opening of the bladder and then extends to the external genitals. The urethra can also connect with the primary urethra at the opening of the bladder and extend into the perineum (also called the Y-type). Type 3 is when there are two bladders that each give rise to a separate urethra that exits through the external genitals.

The clinical features of this abnormality are variable. People with complete urethral duplication can be asymptomatic or can present with a double stream of urine, incontinence, recurrent infections, or outflow obstructions. A double stream is the most common complaint and can be annoying, depending on where the extra opening in the genitals is located.