Effect of multimodal electrical stimulation combined with low-intensity focused ultrasound on endometrial receptivity and clinical pregnancy outcomes in infertile women undergoing freeze-thawed embryo transfer.

We aimed to investigate the effect of multimodal electrical stimulation combined with low-intensity focused ultrasound on endometrial receptivity as well as clinical pregnancy outcomes in infertile women. One hundred women undergoing in vitro fertilization-frozen-thawed embryo transfer were randomly divided into a treatment group and a control group. The treatment group received multimodal electrical stimulation combined with low-power focused ultrasound treatment for 30 min/times per day, once a day, for 7-10 days; the control group did not receive the treatment, and at the end of the treatment each of the two groups underwent frozen embryo transfer. The effect was assessed by the following indicators: endometrial thickness and volume, type of endometrium, endometrial blood flow, uterine artery pulsatility index, resistance index, and uterine arteria peak systolic velocity/end-diastolic velocity values, endometrial peristaltic wave frequency and endometrial volume; biochemical pregnancy rate, clinical pregnancy rate, and embryo implantation rates. uterine artery S/D and uterine artery RI were significantly increased after treatment with statistical differences. The rest of the indicators showed positive changes but no statistical differences. We conclude that multimodal electrical stimulation combined with low-frequency focused ultrasound therapy is effective in improving endometrial receptivity and clinical pregnancy outcomes in infertile women undergoing frozen-thawed embryo transfer.