RESUMEN
Most spinal cord injury (SCI) men have fertility problems caused by anejaculation and a decreased fertility of the ejaculate. There are several methods to induce ejaculation, such as vibratory stimulation and transrectal electrostimulation. In order to investigate the current state of knowledge about the effectiveness of vibratory stimulation and to prepare a controlled clinical trial we reviewed the available literature. Ten articles met our inclusion criteria. Articles were found by various strategies, such as computer searches and screening of relevant journals. We used a structured approach to evaluate these articles. In total 428 patients had been treated with vibration. Sixty percent (257) of the patients responded to treatment, ie produced ejaculate. Because of methodological shortcomings in most studies it remains unclear whether there is a relationship between injury type, such as level and completeness of the injury, and the response rate. Semen analyses showed a large intersubject variation. From the data available, it could be concluded that the semen volume is usually normal, whereas sperm motility and morphology of spermatozoa were in most cases far from normal. Side effects of vibratory stimulation were reported in 6% of the patients. Semen could be used for various (assisted) reproductive technologies, eg artificial insemination, in vitro fertilisation and microinsemination. Therefore, it is very important to know which stimulation method is most effective in treating anejaculatory SCI men. This review of the literature shows that the effectiveness of vibratory stimulation remains unclear. New, well designed clinical trials as well as basic research activities might clarify the effectiveness of vibratory stimulation and transrectal electrostimulation.