The equivalent method in the female is tubal ligation, or tying and cutting the uterine tubes. Vasectomy interrupts the transport of sperm and tubal ligation interrupts the transport of eggs. Tubal ligation carries higher risks than vasectomy because it requires invasion of the peritoneal cavity.
Uterus bicornis occurs when the two paramesonephric ducts fail to fuse during fetal development.
If the corpus spongiosum became as engorged as the corpora cavernosa, the pressure would collapse the urethra and block the passage of semen during ejaculation. The absence of a tunica albuginea around the corpus spongiosum allows it to expand relatively freely, so it does not build up as much pressure as do the more confined corpora cavernosa.
Since the vestibular bulbs function as erectile tissues, it is logical to hypothesize that they are homologous to one of the penile erectile tissues. The corpora cavernosa of the penis are homologous to those of the clitoris, ruling them out. This leaves the corpus spongiosum, which is indeed homologous to the female vestibular bulbs. This is also suggested by the fact that both the corpus spongiosum and the vestibular bulbs encircle the urethra.
Fertilization must occur in the distal one-third of the uterine tube while the oocyte is still alive.
