To evaluate the effects of transcutaneous electrical acupoint stimulation (TEAS) on the pregnancy outcome and sperm parameters in patients with idiopathic oligoasthenospermia.
We searched PubMed, EMBASE, Cochrane Library, CNKI, VIP and Wanfang from inception till January 2020 for randomized controlled trials (RCT) with the keywords male infertility, oligozoospermia, asthenozoospermia, acupuncture, transcutaneous electrical acupoint stimulation, etc. Using the Cochrane risk bias tool, we evaluated the quality of the identified RCTs, and analyzed the primary outcomes, including pregnancy and live birth, and secondary outcomes, such as sperm concentration, motility and morphology.
Four RCTs with 321 subjects were included, of which none reported live birth and only one reported a pregnancy rate of 15% after treatment of 2 Hz TEAS. Neither 2 Hz (WMD: -3.01, 95% CI: -22.28 to 16.26) nor 100 Hz TEAS (WMD: -0.02, 95% CI: -5.29 to 5.56) had any significant effect on sperm concentration, while 100 Hz TEAS markedly improved the percentage of grade a sperm (WMD: 6.83, 95% CI: 2.10 to 11.57) compared with 2Hz TEAS (WMD: 2.31, 95% CI: 1.01 to 3.61). In comparison with the blank control, neither 2 Hz (WMD: 4.07, 95% CI: -5.15 to 13.29) nor 100 Hz TEAS (WMD: 6.59, 95% CI: -5.36 to 18.55) significantly affected the percentage of grade a + b sperm or total sperm motility.
The effect of TEAS on the pregnancy outcome is not yet clear. 100 Hz TEAS significantly improved the percentage of grade a sperm in idiopathic oligoasthenospermia patients, which, however, is to be further verified with more high-quality clinical studies.

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