Gut motility is a movement of the gastrointestinal tract that results in the movement of the food from the mouth through all parts of the tract. The movements are associated with the contractions of the muscle located in the wall of the digestive system. These radial contractions and relaxations of the gut muscles that cause the formation of a moving wave are called peristalsis. Pregnancy is characterized by decreased gut motility and peristalsis due to the effect of high serum concentration of progesterone that induces the relaxation of smooth muscles. Decreased peristalsis in pregnant women leads to constipation, heartburn, and nausea.