5Le Ray C,Fraser W,Rozenberg P,et al.Duration of passive and active phases of the second stage of labour and risk of severe postpartum haemorrhage in low-risk nulliparous women[J].Eur J Obstet Gynecol Reprod Biol,2011,158:167-172. 被引量：1
6Friedman EA.The graphic analysis of labor[J].Am J Obstet Gynecol,1954,68:1568-1575. 被引量：1
8Friedman EA.Labor clinical evaluation and management[M].2nd ed.New York:Appleton-Century-Crofts,1978. 被引量：1
9Zhang J,Troendle J,Mikolajczyk R,et al.The natural history of the normal first stage of labor[J].Obstet Gynecol,2010,115:705-710. 被引量：1
10Zhang J,Landy HJ,Branch DW,et al.Contemporary patterns of spontaneous labor with normal neonatal outcomes[J].Obstet Gynecol,2010,116:1281-1287. 被引量：1
