Research Article

Pain Relief during Oocyte Retrieval by Transcutaneous Electrical Acupoint Stimulation: A Single-Blinded, Randomized, Controlled Multicenter Trial

Figure 3

Changes in serum β-endorphin levels in the women who underwent oocyte retrieval after transcutaneous electrical acupoint stimulation (TEAS) intervention. The serum levels of β-endorphin after oocyte retrieval were significantly higher in the TEAS group compared with the mock TEAS group (unpaired two-tailed Student t-test). The serum levels of β-endorphin after oocyte retrieval were higher than that at baseline in the TEAS group (paired two-tailed Student’s t-test). Data are expressed as means ± standard deviation. .