GASTROSCHISIS AND OMPHALOCELE
Defects in the abdominal wall occur during the early stages of fetal development. Interruption in the normal development of the abdomen between 6 and 10 weeks of gestation prevents normal closure of the abdomen and allows the abdominal organs to float freely in amniotic fluid (Lepigeon, Van Miegham, Maurer, Giannoni, & Baud, 2014). Abdominal wall defects increase neonatal mortality and morbidity, as well as the risk of preterm delivery, neonatal surgery, infection, digestive issues, and prolonged hospitalization. Gastroschisis and omphalocele are the two most common types of congenital abdominal wall defects in newborns (Corey et al., 2014). Gastroschisis occurs once in every 12,000 live births, and omphalocele occurs once in every 4,000 live births (Corey et al., 2014). The increase in incidence of gastroschisis over the past 10 years is concerning and unexplained (Bergholz, Boettcher, Reinshagen, & Wenke, 2014). Currently there is no fetal intervention for gastroschisis or omphalocele and a large number of these pregnancies result in preterm birth (Lepigeon et al., 2014). Surgical correction of gastroschisis and omphalocele is imminent after birth and best managed with a team of specialists (Insigna et al., 2014). Delivery ideally occurs in a center equipped to perform surgery and care for the newborn in a neonatal intensive care unit.
The formation of the abdomen occurs during weeks 6 to 10 of fetal development. During this time, the abdomen lacks sufficient room to accommodate the growth of organs so the intestines naturally protrude into the umbilical cord and then at week 11 recede back into the abdomen (Rubarth & Van Woudenberg, 2016). Failure of the organs to recede prevents closure and allows organs to form outside the abdomen. Gastroschisis and omphalocele are both characterized by herniation of abdominal organs that may include the intestines, spleen, liver, or other organs (Corey et al., 2014). The presence of gastroschisis or omphalocele is generally detected prenatally on a routine ultrasound and an elevated maternal serum alpha fetoprotein (AFP; Lepigeon et al., 2014). Once a defect is identified, repeated ultrasounds are recommended throughout the remainder of the pregnancy to monitor the growth and well-being of the fetus (Lepigeon et al., 2014).
Although the etiology is unknown, there is evidence linking environmental factors and maternal smoking and alcohol ingestion, genitourinary infection during the first trimester, use of selective serotonin-reuptake inhibitors (SSRIs), and poor prenatal care (Insigna et al., 2014). The risk of gastroschisis is highest among women younger than 20 years of age, whereas the risk for omphalocele is noted in advanced maternal age.
149A gastroschisis is herniation typically located to the right of the umbilicus and lacks a membrane or sac to cover the exposed organs. The defect is not associated with chromosomal defects and classified as simple or complex. Simple gastroschisis has intestines or other organs outside the abdomen, whereas complex gastroschisis has additional pathologies of intestinal atresia, perforation, necrotic segments, or volvulus (Bergholz et al., 2014). Complex gastroschisis requires a longer hospitalization and is associated with more feeding complications.