Urethral Sphincter - Sex Differences

Sex Differences

Despite common misconceptions, human males do not have stronger urethral sphincter muscles than females, nor are there any noticeable capacity differences in the bladders. Anatomically, females have to urinate more frequently because their bladders share space with the uterus and vagina in the anterior wall. In males and females, this muscle functions to prevent the release of urine. In males, the internal sphincter muscle of urethra functions to prevent reflux of seminal fluids into the male bladder during ejaculation. In males the bladder does not share space with any reproductive organs.

Females do have a more elaborate external sphincter muscle than males as it is made up of three parts, the sphincter urethrae, urethrovaginal muscle, and the compressor urethrae. The urethrovaginal muscle fibers wrap around the vagina and urethra and contraction leads to constriction of both the vagina and the urethra. The origin of the compressor urethrae muscle is the right and left inferior pubic ramus and it wraps anteriorly around the urethra so when it contracts it squeezes the urethra against the vagina. The external urethrae, like in males, wraps solely around the urethra.

Read more about this topic:  Urethral Sphincter

Famous quotes containing the word differences:

    Quintilian [educational writer in Rome about A.D. 100] hoped that teachers would be sensitive to individual differences of temperament and ability. . . . Beating, he thought, was usually unnecessary. A teacher who had made the effort to understand his pupil’s individual needs and character could probably dispense with it: “I will content myself with saying that children are helpless and easily victimized, and that therefore no one should be given unlimited power over them.”
    C. John Sommerville (20th century)