Fellowship in Sexology and Psychosexual Counseling. For More Info WhatsApp- 9604715783. Ejaculation is an explosive end to the intercourse, a means of propelling the semen into the vagina. The process of ejaculation begins by contraction epididymis, Vas deferens, seminal vesicles and prostate to propel the semen into the prostatic part of urethra. The internal urethral orifice is closed to prevent voiding of urine or flowing of semen into the urinary bladder. Contraction of prostate aided by the pelvic muscles expels the semen into the vagina in five to eight spurts. Erection soon dies down and the penis is limp for some time.