I have lordosis. Will I be laying on back during an endoscopy?

Left lateral side. Most endoscopies are performed with you turned into the left lateral position--this means you are turned onto your left side. This takes advantage of the body's anatomy. Since your stomach is on the left side, turning you to the left allows the endoscope to drop into your stomach. The left position also reduces your risk of aspirating saliva or stomach contents were you instead on your back.