6Martensson L, Wallin G. Use of acupuncture and sterile water injection for labor pain: a survey in sweden[J]. Birth, 2006, 33 (4) : 289.
7Borup L, Wurlitzer W, Hedegaard M, et al. Acupuncture as pain relief during delivery: a randomized controlled trial [ J ] . Birth, 2009, 36 (1): 5.
8Hutton EK, Kasperink M, Rutten M, et al. Sterile water injection for labour pain : a systematic review and meta - analysis of randomised controlled trials [J] . BJOG, 2009, 116 (9) : 1158.
9Adachi K, Shimada M, Usui A. The relationship between the parturient's positions and perceptions of labor pain intensity [ J] . Nursing Research, 2005, 52 (1): 47.
10Campbell DA, Lake MF, Falk M, et al. A randomized controlled trial of continuous labor support in labor by a lay doula [J] . JOGNN, 2006, 35 (4): 456.