The objective of this research was to study whether positive and negative maternal emotional states were related to obstetrical outcomes in 205 women who participated in a study conducted between 2004 and 2007 in the Sant Joan University Hospital of Reus, Spain. Maternal anxiety and positive emotional states were assessed using the State Trait Anxiety Inventory. The obstetrical outcomes of interest were gestational age at birth, birth weight, and mode of delivery. More women with lower anxiety levels and a more positive state of mind had normal deliveries. Anxiety was related to lower birth weight and to difficult delivery. A positive state of mind and emotional stability were associated with having a normal delivery. Therefore, moderate levels of anxiety were associated with complications during delivery and poorer fetal outcomes, whereas a positive state of mind was associated with better childbirth experiences.