THE MALE SEXUAL ORGANS: NERVOUS MECHANISM OF EJACULATION
The process of ejaculation is a highly complex mechanism—more intricate than erection—involving not only the accessory sexual organs (epididymis, ductus deferens, seminal vesicles and prostate), but also the pelvic muscles to propel the semen into the vagina. The sympathetic nerve, where stimulation causes stress and loss of erection, is also responsible for ejaculation.
Let us analyse the complicated process of ejaculation. Imagine that Explorer XY is on the launching pad ready for a voyage lo the planet Venus—the vagina of your partner. The countdown now begins.
Explorer XY is launched into (her) space. As it zooms to and fro it becomes a beehive of activity, sending innumerable messages to the control tower (the brain) from the vagina—the resistance offered by it, the humidity and the temperature. If we now imagine a situation where due to metal fatigue or a short circuit, the rocket blows up, similarly ejaculation is an explosive end to intercourse, a means of propelling the semen into the vagina. The process of ejaculation begins by contractions of the muscular coat of the epididymis, ductus deferens, seminal vesicles and the prostate to propel the semen into the prostatic part of the urethra. The internal urethral orifice is sealed off to prevent voiding of urine or flowing of the semen into the urinary bladder. Powerful contractions of the prostate aided by the pelvic muscles expel the semen into the vagina in six to eight strong squirts. Erection soon dies down and the penis is limp and lifeless for some time and then the process starts all over again.
Men's Health-Erectile Dysfunction