A randomized trial of increased intravenous hydration in labor when oral fluid is unrestricted.

BACKGROUND AND OBJECTIVES Increased intravenous (IV) hydration is associated with decreased labor duration and oxytocin augmentation in nulliparous women when oral fluid is restricted. The objective of this study was to determine the effect of increased IV hydration on the duration of labor when access to oral fluid was unrestricted. METHODS Term, nulliparous women with uncomplicated singleton pregnancies were randomly assigned to receive lactated ringers at 250 ml per hour (IV fluid group) throughout active labor or usual care. All women were allowed unrestricted access to oral fluids. RESULTS Eighty women completed the study, 37 in the IV fluid group and 43 in the usual care group. There was no difference in the primary outcome of total duration of labor (9.5 versus 9.4 hours) or in the secondary outcomes of duration of the first stage (7.9 versus 8.0 hours), duration of second stage (1.6 versus 1.4 hours), or rate of oxytocin augmentation (51% versus 44%). CONCLUSIONS Increased IV hydration does not decrease labor duration in nulliparous women when access to oral fluid is unrestricted.