The efficacy and mechanism of acupuncture in the treatment of male infertility: A literature review

Male infertility has become a growing public health concern, affecting approximately 50% of couples with reproductive difficulties. This problem not only impacts the chances of reproduction but may also serve as an early indicator of other health conditions, including cardiovascular and metabolic disorders and even increased mortality risk. With the implementation of family expansion policies in several countries, the social and economic pressure on couples facing fertility problems has intensified significantly. Conventional treatments for male infertility, although available, often present important limitations in terms of efficacy, high cost, and adverse effects, leading many patients to seek complementary approaches such as acupuncture.

This study is a comprehensive review of the scientific literature on the use of acupuncture in the treatment of male infertility, analyzing both the efficacy and the mechanisms of action involved. The researchers conducted a systematic search in two important databases, PubMed and CNKI, covering studies published between January 1985 and January 2022. The methodology included the analysis of different types of scientific studies, ranging from controlled clinical trials to animal experiments, meta-analyses, and systematic reviews. The search terms used were broad and specific, including "male infertility," "oligoasthenozoospermia," "varicocele," "erectile dysfunction," "premature ejaculation," "genital inflammation," and various acupuncture modalities such as electroacupuncture and transcutaneous electrical acupoint stimulation.

The results of the review demonstrate promising evidence on the efficacy of acupuncture across multiple aspects of male infertility. With regard to semen parameters, which are considered fundamental indicators of male fertility, several studies have shown that acupuncture can significantly improve sperm concentration, motility, and morphology. A prospective controlled study found significant increases in virtually all semen parameters after acupuncture treatment, including total functional sperm fraction, percent viability, and axoneme integrity. Other studies have demonstrated that both low-frequency and high-frequency electrical stimulation can improve sperm motility in patients with asthenozoospermia.

The mechanisms by which acupuncture improves semen quality appear to involve regulation of several molecular pathways, including modulation of cytoskeletal proteins of Sertoli cells and improvement in germ cell proliferation with reduced apoptosis.

In the treatment of varicocele, one of the most common and treatable causes of male infertility, acupuncture has shown results comparable to those of surgery. A randomized study directly compared the efficacy of acupuncture with subinguinal microsurgical varicocelectomy, finding that the increase in sperm concentration was significantly greater in the acupuncture group, with equivalent pregnancy rates in both groups. The proposed mechanisms include improvement of testicular blood flow, reduction of scrotal temperature through heat exchange in the pampiniform plexus, and disruption of peroxidation processes. Experimental studies have demonstrated that acupuncture can significantly increase the activity of antioxidant enzymes such as superoxide dismutase and catalase, while decreasing the levels of harmful oxidative substances such as malondialdehyde and nitric oxide in testicular tissue.

For reproductive system infections, which affect 12% to 35% of infertile men, acupuncture has shown benefits both in symptoms and in semen parameters. A large study with 440 men with prostatitis demonstrated that eight weeks of acupuncture treatment significantly improved urinary symptoms, pain, and sexual function, with an efficacy rate of 60.6%. The anti-inflammatory mechanisms of acupuncture appear to involve inhibition of cyclooxygenase synthesis and reduction of inflammatory factors such as TNF-α and IL-1β. With regard to male sexual dysfunctions, including erectile dysfunction and premature ejaculation, several studies have demonstrated that acupuncture may be superior to placebo.

A prospective randomized study showed that 68.4% of patients with psychogenic erectile dysfunction responded satisfactorily to acupuncture, compared with only 9% in the placebo group.

The clinical implications of these findings are significant for both patients and health care professionals. For patients, acupuncture represents a safe therapeutic option, with few adverse effects and relatively low cost compared with conventional treatments. The review identified six main acupoints frequently used in the treatment of male infertility: Guanyuan (CV-4), Shenshu (BL-23), Mingmen (GV-4), Sanyinjiao (SP-6), Taixi (KI-3), and Zusanli (ST-36). These points can be adapted according to different diagnostic patterns of traditional Chinese medicine.

For health care professionals, the evidence suggests that acupuncture may be considered as adjunctive or alternative therapy, especially in cases where conventional treatments are contraindicated, ineffective, or cause significant adverse effects. The combination of acupuncture with conventional therapies may potentiate therapeutic outcomes, offering an integrative approach to the treatment of male infertility.

However, the review also identifies important limitations in the current evidence. Many of the studies analyzed had small sample sizes, lack of adequate blinding, or non-randomized methodological designs, which may compromise the reliability of the results. There is also controversy in the literature, with some studies finding no statistically significant differences between acupuncture and sham acupuncture in in vitro fertilization outcomes. A recent meta-analysis suggested that acupuncture alone does not show clear superiority over medications or sham acupuncture in improving semen quality.

In addition, there is an inherent tension between the standardization required for rigorous clinical trials and the traditional individualized approach of Chinese medicine, where acupoint selection is based on diagnostic patterns specific to each patient.

In conclusion, although current evidence suggests that acupuncture may be beneficial for several aspects of male infertility, including improvement of semen parameters, treatment of varicocele, and management of sexual dysfunctions, more rigorous studies with greater statistical power are still needed. Acupuncture appears to be a safe and potentially effective option, especially when used as complementary therapy alongside conventional treatments. Future research should focus on randomized controlled clinical trials with larger samples, better blinding, and more robust methodology to provide definitive evidence on the role of acupuncture in the treatment of male infertility. In the meantime, health care professionals may consider