Gastroschisis is a birth defect where the abdominal wall does not fully develop while a baby is inside the womb. The exact cause of this condition is not clear.
Usually, the intestine starts to develop inside the umbilical cord and then moves inside the baby’s abdomen later on in the pregnancy. However, in gastroschisis, abnormal development of the abdominal wall means the intestine continues to develop outside of the abdomen and is exposed to the open air when the child is born.
The abdominal wall usually develops through invagination of the cranial, caudal and lateral embryonic folds. As the abdominal wall is developing, the intestine moves into the umbilical cord during the sixth week of gestation. The abdominal wall is fully formed by the 10th to 12th week of gestation, at which point the intestine moves back inside the abdomen.
Gastroschisis is thought to arise due to ischemic insult or a lack of blood flow to the developing abdominal wall. The area near the umbilicus is most likely to be affected because it is supplied by the right umbilical vein and right omphalomesenteric artery until they fold inwards.
Some of the risk factors for developing gastroschisis include:
- Teenage pregnancy
- Smoking during pregnancy
- Drug or alcohol abuse during pregnancy
- The use of vasoactive over-the-counter drugs (such as pseudoephedrine) have also been associated with gastroschisis.
- Other risk factors associated with gastroschisis include low birth weight, exposure to environmental toxins and the use of oral decongestants during pregnancy.
Reviewed by Sally Robertson, BSc