Sex organs, commonly called the genitalia by scientists, are the body structures involved in sexual reproduction. They are also related to the passage of urine in humans: in males the urethra runs through the penis, while in females the urinary opening is separate from the reproductive tract (urination). Many animals have specialised reproductive organs; this article concentrates on those of human beings.

Anatomy and function

Human genitalia include external and internal parts. Their primary role is reproduction — producing, transporting and, in females, supporting the development of new life. They also participate in sexual pleasure and, in some cases, the elimination of urine.

Male reproductive organs

  • Penis — the external organ used during sexual activity; contains the urethra, which conveys urine and semen.
  • Scrotum — the pouch of skin that holds the testicles and helps regulate their temperature.
  • Testicles — glands inside the scrotum that generate sperm and the hormone testosterone, the latter contributing to male physical development and secondary sexual characteristics.
  • Accessory glands (for example the prostate and seminal vesicles) secrete a fluid that mixes with sperm to form semen, which is expelled during ejaculation.

Female reproductive organs

  • Vulva — the collective name for the external female genital structures surrounding the vaginal and urethral openings.
  • Vagina — the muscular canal leading to the internal reproductive organs; it receives the penis during sexual intercourse and serves as the birth canal.
  • Uterus — also called the womb; a muscular organ where a fertilised egg implants and a fetus develops during pregnancy.
  • Ovaries — the organs that release ova (egg cells) and produce hormones such as estrogen, which influence female development and reproductive cycles.
  • Fallopian tubes — the passages that carry ova from the ovaries toward the uterus and where fertilisation commonly occurs.

Attitudes toward nakedness and the display of genitalia vary widely between cultures. In many societies people are prudish about public exposure of genitals; laws against public indecency restrict when and where nudity is permitted. Designated spaces such as nudist colonies exist in some places for people who prefer social nudity.