 However, the duration of active first stage (from 5 cm until full cervical dilatation) usually does not extend beyond 12 hours in first labours ("primiparae"), and usually does not extend beyond 10 hours in subsequent labours ("multiparae").The median duration of active first stage is four hours in first labours and three hours in second and subsequent labours.Dystocia of labor, also called "dysfunctional labor" or "failure to progress", is difficult labor or abnormally slow progress of labor, involving progressive cervical dilatation or lack of descent of the fetus.