Promotion on labor process and relief of the low back pain by relaxing pelvic muscle with Shangliao (BL 31) point injection in women using epidural analgesia during labor: A randomized, controlled, clinical trial

Abstract

BackgroundThe purpose of this study was to explore the effects of combing Shangliao point injection with epidural analgesia on labor pain and birth process in women with low back pain and the possible mechanisms. Methods93 consecutive women were randomized to receive either Shangliao point injection combined with epidural analgesia or epidural analgesia. Another 14 women were recruited to explore the mechanisms and the transperineal ultrasound was performed accordingly. ResultsThe main result duration from epidural analgesia to baby delivery was significantly shorter in epidural analgesia and saline injection group than that in epidural analgesia group 307.0 (175.0–445.0) min VS 369.0 (254.0–563.0) min (P = 0.02). The verbal numerical rate scaling score in low back during the first contraction was significantly decreased 5.0 (4.0–7.0) after Shangliao point injections (P < 0.001). The consumption of ropivacaine per hour was significantly less in epidural analgesia and saline injection group than in epidural analgesia group (−0.4 mg, 95%CI: −0.1 to −1.8; P = 0.03). The angle of progression and anteroposterior diameter of the levator hiatus at rest and during valsalva were significantly increased after shangliao point injection (7.10°, 95%CI, 1.50~12.70; P = 0.02); (9.10°, 95%CI, 3.60~14.58; P < 0.01); (0.27 cm, 95%CI, 0.03~0.51; P = 0.03); (0.30 cm, 95%CI, 0.13~0.48; P < 0.01). ConclusionsShangliao point injection could shorten the time to baby delivery and rapidly relieve low back pain in addition to epidural analgesia, that may attribute to its function of relaxing the pelvic floor muscles and promote fetal head progress.