Retrograde semen is retrograde ejaculation in men, where the retrograde semen after ejaculation can pass out of the body in the urine. Retrograde ejaculation is when the semen after ejaculation does not flow out of the external urethral orifice, but instead flows into the bladder. Retrograde ejaculation is mainly due to the dysfunction of the bladder neck muscles and some muscles of the posterior urethra in men, resulting in the loss of the contraction function of the internal sphincter of the bladder, so that the semen flows back into the bladder during ejaculation. So during urination, the semen that flows into the bladder is expelled from the body along with the urine. Retrograde ejaculation may be related to anatomical structural abnormalities or congenital diseases, urethral diseases, surgical injuries, neurological factors, and drug factors. Among them, retrograde ejaculation caused by transurethral resection of the prostate is more frequent. When men have retrograde ejaculation, it is recommended to seek medical treatment in time and choose a reasonable treatment plan under the doctor’s comprehensive analysis.