Snapshot A 33-year-old G1P0 pregnant woman presents to the hospital at 41 weeks of gestation with contractions. She notes that she attended all of her prenatal appointments and had an uncomplicated pregnancy. She requests spinal-epidural anesthetics to alleviate her pain. After 5 hours of labor with adequate contractions (> 200 Montevideo units), her cervix is found to be dilated to 8cm with ruptured membranes. Introduction Overview abnormal labor occurs when the milestones of normal labor, in which uterine contractions result in progressive dilation and effacement of the cervix, are not reached Epidemiology 8-11% of deliveries are complicated by an abnormal first stage of labor ETIOLOGY Pathophysiology results of problems with the 3 P'S pelvis login to view 1 more bullet passenger login to view 2 more bullets power login to view 2 more bullets Presentation Symptoms prolonged contractions Physical exam delayed cervical dilation prolonged/protracted labor if cervical dilation is < 1.2 cm/hour (primipara) or 1.5 cm/hour (multipara) login to view 1 more bullet delayed cervical effacement Studies Labor curve plot the patient's labor progress (cervical dilation vs. duration in hours) Intrauterine pressure monitoring an intrauterine pressure catheter is used to measure the strength of uterine contractions Fetal heart tracing monitor for reassuring fetal heart rate patterns throughout the labor course Treatment Medical repositioning the patient use of a "peanut ball" may decrease the length of the first and second stages of labor oxytocin indications login to view 2 more bullets Surgical amniotomy indications login to view 3 more bullets operative vaginal delivery or cesarean delivery indications login to view 1 more bullet Complications Hyperstimulation of the uterus may result from prolonged medical induction of labor can result in several complications uterine rupture postpartum uterine atony postpartum hemorrhage Chorioamnionitis increased risk when rupture of membranes occurs for > 18 hours administer antibiotics Prognosis Likelihood of abnormal labor in subsequent pregnancies depends on the cause for abnormal labor i.e. if abnormal labor was due to small contours of the pelvis that were inadequate for a normal or small-sized infant, then the likelihood for recurrence is high