This is a prospective cohort study including primiparous women in active phase of labor at term pregnancy on admission at the delivery ward at Linkoping University hospital. The study period was between October 2014 and March 2016. Term pregnancy was defined as ≥ 37 - ≤ 42 gestational weeks. The women had to be in active labor according to the Swedish definition; two out of three of the following criteria must be present: painful contractions (two to three contractions in every ten minutes), cervix shortened and dilated > one centimeter (cm) and/or rupture of membranes. The maximum cervix dilatation allowed for inclusion was seven cm. Further the participant had to be proficient in the Swedish language and aged ≥18 years. All participants were given written and verbal information of the study. The verbal consent to participate was documented in the women´s medical record.