In 2004 Mark Landon and his colleagues in the United States published “Maternal and Perinatal Outcomes Associated with a Trial of Labor after Prior Cesarean Delivery,” which compared the risks of vaginal delivery and cesarean section for delivery of a fetus after a previous cesarean delivery. During a cesarean section, a physician surgically removes a fetus from a pregnant woman through an incision in her abdomen. By the late 1900s, most clinical guidelines viewed attempting a vaginal birth after a previous cesarean delivery as a reasonable option for most women. Yet, physicians often noticed an increased risk of uterine ruptures as more patients underwent vaginal deliveries following previous cesarean sections. As such, many physicians continued to recommend cesarean deliveries for women who had a past cesarean section. Landon and his team evaluated the risks of both delivery methods and published their results in the New England Journal of Medicine in 2004. In “Maternal and Perinatal Outcomes,” the authors found that there was no significant difference between the risks of vaginal birth after cesarean and repeat cesarean sections, providing more evidence for clinical guidelines recommending vaginal births after cesarean sections.