The aims of the thesis were to develop a measure of fear during labor and to investigate women's experiences of fear and pain during labor and delivery as well as their levels of stress hormones. We also wanted to explore the associations between fear, pain, stress hormones and the duration of labor. Finally, we aimed to examine the relationships between pre-and postpartum fear, and fear and pain during labor.The measurement of fear was developed in two substudies. First we composed a list of 60 fear-related items and their contrasts and tested it in a group of 92 women in labor. After psychometrical analyses, 10 items were selected for the final scale. The scale was then tested in another group of 57 women in labor. Via semi-structured interviews the content of the items was documented and analyzed.Fifty-five nulliparous women participated in the investigation of women's experiences of fear, pain, levels of stress hormones and duration of labor. During gestation weeks 37-39, we measured levels of fear of childbirth, urinary catecholamines and salivary cortisol. During labor, hourly measurements were performed of fear, pain and levels of stress hormones. Finally, at two hours, two days and five weeks postpartum, fear of childbirth and stress hormones were measured.The questionnaire that measures fear during labor was called the Delivery Fear Scale (DFS). The DFS has an alpha coefficient of .8 and has good psychometric qualities in both nulliparous and parous women. It takes women in labor between 30 and 90 seconds to listen to and answer all the statements. We found that nulliparous women had higher fear during phase 1 of labor (cervix dilatation 3-Scm) than parous women. Fear during phase 1 of labor predicted the total amount of pain relief received during labor, but not the duration of remaining part of labor, nor the occurrence of instrumental vaginal delivery or emergency cesarean section.The results from the subsequently studies showed that there was an increase of the levels in stress hormones from pregnancy to labor. Epinephrine and cortisol increased more than 500% and norepinephrine approximately 50%. In women without EDA fear and cortisol increased throughout labor. In women with EDA cortisol did not increase, fear, pain and catecholamine levels first decreased after the administration of EDA but at the end of labor fear and pain increased. In phase 1, fear, but not pain, was more intensive in women who later subsequently received EDA than in those who did not. Fear and pain correlated positively during labor. A high level of epinephrine was associated with a shorter duration of phase 1 of labor. Postpartum fear of childbirth was higher in women who had received EDA during labor than in those who had not. Pre- and postpartum fear of childbirth correlated positively with fear but not with pain during phase 1 of labor.In conclusion, DFS is a new measure of fear during labor with good psychometric qualities. Childbirth is a stressful event associated with exceptionally high levels of stress hormones. In this study women's experiences of fear and pain were associated throughout labor. The administration of EDA heavily influenced the course of fear, pain and stress hormones. Women who later received EDA had higher scores of fear but not of pain early during labor than those who did not receive EDA. Late pregnant women who fear childbirth are prone to have a fearful delivery, as reported during the actual labor and postpartwn.