Caesarean section delivery is the most common operation performed in the United States, according to a 2009 survey. The World Health Organization has recommended that the percentage of caesarean section delivery in any country of the world should not be more than fifteen percent. The United States had a caesarean birth rate of thirty one percent in the year 2006, and the rate has increased since that time. The first caesarean section delivery took place in Ancient Rome, during the time of Julius Caesar, and it is speculated that the procedure was named after him. Women always died after a caesarian section delivery until around 1500, so the procedure was only done as a last resort to save the life of a child. Even today, a caesarian section delivery increases the risk of problems when compared with vaginal birth. In subsequent pregnancies, women can have serious problems with the placenta, or the scar in the uterus can rupture. Babies are at increased risk for a spinal cord injury, a brain injury, or some sort of physical abnormality when brought into the world via a caesarian section delivery.