Urethra

The urethra is a tube that connects the reproductive system and bladder to the outside of the body to transport urine and sperm. All mammals have it. It allows the removal of urine from the body. There is a muscle (the urethral sphincter) which controls urination.

In male mammals, the urethra is also a part of the reproductive system, because males use it as a tube for sperm during sex. The urethra joins together with the ejaculatory duct in the prostate to meet the reproductive system.

Human anatomy

In human anatomy, a male person has a longer urethra than a female person. This means that the latter have bladder infections more often because their bladders are closer to the outside. Because the male urethra is longer and is not straight, inserting a catheter (tube to help urination) is more difficult for a male person.

Male

In male anatomy, the urethra is about 20 cm (8 in) long and its opening goes to the outside of the body. It ends at the opening of the penis. For a male person, the urethra goes through the penis. The section that goes through the prostate is about 3-4 cm long.

The male urethra has three sections:

The prostatic urethra crosses the prostate gland. The vas deferens also opens into the urethra in this section.
The membranous urethra is a short section that goes through the urethral sphincter. It is 1 or 2 cm long and is the narrowest (least wide) part of the urethra.
The spongy or penile urethra goes through the penis on its lower side. This section is 15-16 cm (6 in) long and goes through the corpus spongiosum.

Female

In female anatomy, the urethra is 3-4 cm (1.5 in) long. The opening to the outside of the body here is part of the vulva (the female area between the legs). The female urethra is between the clitoris and the opening to the vagina.

The female bladder can get infections more often because the bladder is closer to the outside. The female urethra is straight.

Medical problems

Urethritis is an infection of the urethra. It often causes pain when urinating.
Kidney stones that go through the urethra can cause a lot of pain.

Medical procedures

To send a tube up the urethra to help drain urine is a common type of catheterization.
To send a tube up the urethra to see the inside of the bladder is called cystoscopy.

Urinary system (edit)
Kidneys \| Ureters \| Urinary bladder \| Urethral sphincters \| Urethra

Human reproductive system
Female anatomy	Female reproductive system – Breasts – Cervix – Clitoris – Fallopian tubes – Bartholin's glands – Gräfenberg spot (G-spot) – Hymen – Labia – Ovaries – Skene's glands – Urethra – Uterus – Vagina – Vulva
Female physiology	Menstruation – Pregnancy – Childbirth – Lactation – Estrogen – Orgasm – Ovum
Male anatomy	Male reproductive system – Bulbourethral glands – Corpus cavernosum – Ejaculatory ducts – Epididymis – Foreskin – Frenulum – Glans penis – Penis – Prostate – Rete testis – Scrotum – Seminal vesicles – Seminiferous tubules – Sertoli cell – Spermatic cord – Testicles (testes) – Urethra – Vasa deferens (Vas deferentia)
Male physiology	Ejaculation – Erection – Orgasm – Semen – Sperm – Testosterone
Anatomy is the study of the parts of the body • Physiology is the study of how the body works