We systematically reviewed seven clinical trials investigating the effects of rTMS on CPPS. Patients receiving repetitive rTMS had higher SF-36 scores and lower pain compared to controls. These effects lose significance at one month after the last treatment. In addition, there was no reduction in anxiety and depression, no reduction in various symptom scores, and a new non-significant correlation between pain severity and rTMS stimulation parameters.
We found that pain intensity, as measured by VAS scores, improved in repeated stimulation studies, and that improvement was also significant in a single case report  that was not included, but did not meet the inclusion criteria of the meta-analysis.
Considering that most of the articles had poor double-blind effect, the trial allocation was not randomized, and the resulting outcome measures were quite different. The heterogeneity of the results of this study is generally not applicable because the anxiety, depression and symptom evaluations cannot be globally evaluated because different measurement tools are used in each survey.
In our analysis, 7 studies included 6 on motor cortex[15, 20, 22–25] and only one on prefrontal cortex. All seven studies analyzed used HF-rTMS as single or repetitive stimulation. Several studies have also confirmed the more significant effect of Hf-rTMS stimulation of the M1 region on chronic pain[33–36], and there are also systematic reviews that have studied the effect of Hf-rTMS stimulation of the dorsolateral cortex prefrontal on chronic pain, and their studies have shown the short-term, mid-term and long-term analgesic effects of transcranial magnetic stimulation on neuropathic pain in the DLPFC. This is why the results of the follow-up period are presented in this article; however, due to the incomplete recording of data, there was no significant difference in pain intensity one month after the last treatment. A recent meta-analysis concluded that Hf-rTMS has therapeutic implications for the motor cortex for a variety of diseases, including not only chronic pain, but also depression and anxiety. In several studies [38, 39], symptom scores were not limited to the evaluation of the disease itself, but also included gastrointestinal function evaluation and urinary function evaluation. Therefore, the analysis of the results of this study used the pain score as the primary measure and also included mood, symptoms, and quality of life evaluations. However, the exact mechanism of action by which rTMS affects pain is unknown. The mechanism of labor pain in M1 and DLPFC  area by transcranial magnetic stimulation may involve direct inhibition of spinal transmission of nociceptive signals. A review has shown that rTMS of prominent axons and local interneurons activated at high frequencies (10 or 20 Hz) has established that cumulative pain can be reduced for at least a few weeks after 10 consecutive working days; the pain-reducing effect of transcranial magnetic stimulation is also considered to be mediated through subcortical neural networks and is the result of enhancement of the dopamine-opioid system, and it has also been reported that transcranial magnetic stimulation therapy can increase serum-endorphin concentrations[16, 19, 34].
In the study, through the analysis of stimulation parameters, all studies were high-frequency stimulation, of which the intensity was 110% rMT in two studies and 80% rMT in five studies. There were very few studies comparing the stimulation intensity, but some studies  had shown that different intensities would have an effect. The study by Zheng et al.  showed that rTMS had a more significant effect on cerebral blood flow at high intensity, and the intensity effect was greater than the frequency effect. However, in the results of this meta-analysis, the 95% confidence interval of the high-intensity group was larger than that of the low-intensity group, the difference was not significant, and the pain intensity of the experimental group was reduced after repeated stimulation. However, it cannot be stated that the strength has no effect on the difference in the results, mainly because the included article is not a randomized controlled trial with a strictly designed protocol.
In particular, the results of this article include two studies of the relationship between pain and bowel sensation during transcranial magnetic stimulation, one study measured rectal and anal pain and sensory thresholds, and concluded that rTMS at 10 Hz appears to mainly change anal and rectal pain with little effect on anorectal sensation, and the other study concluded that transcranial magnetic stimulation of the primary motor cortex improves maximum rectal tolerance in IBS patients with significant allergy. Both of them provide a basis for IBS in neurostimulation therapy and also lay the foundation for the improvement of CPPS in terms of gastrointestinal conditions.
Two studies reported mild and transient headache, nausea, inappropriate site of stimulation, and some neurobehavioral adverse events, which were common adverse reactions to TMS and resolved spontaneously in a short period of time. There were no serious adverse events reported, and the serious adverse event of transcranial magnetic stimulation was epilepsy, which was not observed in this study.
The strengths of our study lie in several aspects. First, we present the first extensive summary of rTMS for the treatment of this disorder in CPPS. Secondly, for the first time, the comparative analysis of rTMS in the treatment of CPPS under different intensity stimulation parameters; third, we included the latest clinical trial articles, providing a reference basis for subsequent treatment and research.
The present meta-analysis also has several limitations. First, the number of participants in all included studies was small, and patients' demographics, study design, and stimulation parameters were heterogeneous. Second, all included studies had a female preponderance. Although no correlation between treatment effect and gender was found in the meta-analysis, in fact, the incidence of CPPS in men was not low, but their study was biased towards medical and surgical treatment. Third, the diagnostic inclusion and evaluation criteria used were different. CPPS contains diverse diseases, and three studies are the same studies but their symptom diagnosis and classification are not the same. Fourth, most of the included surveys allowed concurrent medication and other treatments during the study period. Therefore, the majority of transcranial magnetic stimulation is used as an adjuvant therapy, and the results receive interactions between drugs and other treatments, and the effectiveness of rTMS alone needs further validation. Fifth, due to insufficient data and high heterogeneity among studies, we failed to complete the group analysis of stimulus flapping, adjuvant therapy for participants, its relationship with symptom improvement, and adverse effects. However, these results are important for assessing the treatment of chronic pain, and a large number of trials are needed in the future to confirm the results in this regard. Finally, although no serious adverse events were reported, the relatively small number of participants in most studies may have affected the accident rate and needs to be illustrated by studies based on large samples for a long time with a single disease.
Future research in this field should still be the focus, and many trials with more perfect standards are needed. For example, the CPPS diagnostic criteria and treatment recommendations of the EUA guidelines are uniformly used; based on a reasonable and statistically significant sample size, a more objective randomized design trial is conducted; it is recommended to use the CPPS pain and urinary symptom scoring scale, and use the male and female CPPS measurement tools recommended by the specifications according to gender differences; and there is also a great need for mechanistic studies, both from cortical mechanisms and from peripheral mechanisms.