EEJ, rectal electroejaculation, REE, trans-rectal electro-ejaculation, TREE
Electroejaculation is a procedure used to obtain semen samples from sexually mature men through electrical stimulation (Pic. 1). The procedure is used in the treatment of:
Electroejaculation is one of the several techniques now available to harvest viable sperm for the purposes of artificial insemination or in vitro fertilization (IVF).
Electroejaculation is most often treatment of option in patients after spinal cord injury (SCI). In those patients, Functional Electrical Stimulation (FES) is a treatment that applies small electrical charges to a muscle that has become paralysed or weakened, due to damage in brain or spinal cord. The initial goal of FES technology is to provide greater mobility to the patients after spinal cord injury.
In humans, electroejaculation is usually carried out under a general anesthetic. An electric probe is is lubricated and inserted into the rectum adjacent to the prostate gland. The probe is activated for 1–2 seconds, referred to as a stimulus cycle. Ejaculation usually occurs after 2–3 stimulus cycles. The stimulus voltage stimulates nearby nerves, resulting in contraction of the pelvic muscles and ejaculation.
The ejaculate is collected from the urethra and prepared for use in artificial insemination. Electroejaculation has also been used for cryoconservation (restoration using freeze).
Erectile dysfunction, ejaculatory dysfunction and poor semen quality are the main causes of infertility in men with spinal cord injury (SCI). Different sperm retrieval techniques such as penile vibratory stimulation (PVS), electro-ejaculation (EEJ) or surgical sperm retrieval (SSR) associated or not with sperm cryopreservation can be offered to these patients to preserve their fertility. If fatherhood cannot be achieved naturally, assisted reproductive techniques can be offered to these patients using either fresh or frozen/thawed sperm. In case of PVS and EEJ failure, surgical sperm extraction (SSR) can be performed.
Caution need to be taken in men with SCI who have a history of autonomic dysreflexia (involuntary nervous system overreacts to external or bodily stimuli) as electroejaculation can cause a significant increase in blood pressure and heart rate.
One thing that should be pointed out is that anesthesia is essential during electroejaculation as the form of rectal injury. The stimulation is given from the minimum voltage of 2 V, and it can be gradually increased 1–2 V per time. The stimulation lasted 6–10 seconds, and one followed another in 15–20 seconds until ejaculation occur. The maximum voltage should not be higher than 18 V. When patients ejaculated, the stimulation should stop immediately, or retrograde ejaculation occurs.
Insufficient sperm parameters in SCI patients
It is known that conventional semen parameter analyses provide insufficient information for the evaluation of male fertility potential and in distinguishing between infertile and fertile men. Reactive oxygen species (ROS) decrease the ability of spermatozoa to fertilise the egg by damaging the sperm membrane, which impairs its motility, and by damaging sperm genetic material (DNA), which impairs its genomic contribution to the embryo, because defective sperm DNA is negatively associated with fertility. To our knowledge, the long-term stability of sperm DNA and ROS levels in SCI patients has not been established. As a result, proper electroejaculation may not lead to collection of satisfactory semen sample.
Care must be taken when using currents greater than 500 mA, as tissue burns may result due to heating of the probe. Another problem with electro-ejaculation is that, the secretions of the accessory glands may not be present in the usual proportions, which may have a detrimental effect on sperm survival.
If live sperm are retrieved, they should be frozen and stored; however, if no live sperm are retrieved, EEJ and/or surgical sperm extraction should be proposed only to patients whose future goals include biological fatherhood. After collection, the semen is used in assisted reproduction.
Prospective studies on the evolution of semen parameters, ejaculatory dysfunction, post-infectious obstructions and spermatogenesis impairment in chronic SCI patients are urgently needed to provide robust data for the evidence-based management of SCI patients’ fertility. Even if use rates are expected to be low, sperm banking may be a simple and affordable preventative measure for selected male SCI patients.