Immediate Effect of Electro-acupuncture on Endometrial Blood Flow in Patients with Recurrent Implantation Failure: A Randomized Controlled Trial.

Objective: To investigate the immediate effects of electro-acupuncture (EA) on endometrial blood flow among recurrent implantation failure (RIF) patients.

Methods: Eighty RIF patients, enrolled from March 2022 to December 2022, were randomly allocated into either the EA group (40 cases) or the waiting-list (WL) group (40 cases) by using a random number table. The EA group underwent acupuncture at points of Shenting (GV 24), Baihui (GV 4), Benshen (GB 13), bilateral Zigong (EX-CA 1), Huangshu (KI 16), Sanyinjiao (SP 6) and Xuehai (SP10), and electric acupuncture apparatus was connected to EX-CA 1, KI 16, SP 6, and SP 10 with disperse-dense waves at 4/20 Hz frequencies for 30 min after transvaginal ultrasound, while the WL group received no intervention. The primary outcome measured was the endometrial volume blood flow. The secondary outcomes included the bilateral uterine artery index, endometrial volume, endometrial blood flow type, vascular distribution index (VI) for endometrial and ovary, clinical pregnancy rate, and embryo implantation rate.

Results: In the EA group, there was a notable decrease in the bilateral pulsatility index and a significant improvement in the endometrial blood flow type post-EA (P<0.05). Both the endometrial blood flow type and VI for the endometrium and right ovary were markedly higher in the EA group compared to the WL group post-treatment (P<0.05). Conversely, no significant disparities were observed in vascular index, flow index, vascular blood flow index, uterine arterial blood flow indices, endometrial volume, clinical pregnancy rate and embryo implantation rate between the two groups after treatment (P>0.05). Besides, no adverse events related to EA were observed.

Conclusions: EA can promptly ameliorate VI for the endometrial and right ovary, and endometrial blood flow type. Future randomized controlled trials are warranted to investigate the long-term effects of EA on blood flow of RIF patients and its implications for pregnancy outcomes. (Trial registration No. ChiCTR2200057377).