At week 8 in gestational development the developing gut herniates out of the embryo and undergoes significant growth. At week 10, this rotates and is reabsorbed into the abdominal cavity. Failure to completely reabsorb the gut and rotate properly can result in a number of defects. Gastroschisis is failure to completely reabsorbed the gut, leaving some outsice the abdomen, with no covering. http://perinatology.com/Reference/Fetal%20development.htm
B) Midgut volvulus- occurs as a result of malrotation as the gut is reabsorbed. Ordinarily the cecum is held to the back of the RLQ by fibrous bands. In the event of midgut volvulus, these bands (Ladd's bands) are still attached to the now displaced cecum in the RUQ; the compress on the intestines, preventing food from moving through and often causing bilious vomiting in newborns. C) Omphalocele- a defect similar to gastroschisis, but covered by the omphalocele sac. D) Umbilical hernia- the gut is entirely reabsorbed in the abdomen, but a defect in the muscular wall overlying it allows omental fat or gut to slip through and bulge out near the umbilicus, still beneath the skin. This hernia is usually reducible with pressure. E) Urachal fistula- failure of the urachus to close, resulting in the leaking of urine from an opening near the umbilicus.