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A 26-year-old woman, G2P1, comes to the emergency department in active labor. She has not received prenatal care during this pregnancy. A 3500g boy is delivered by an uncomplicated vaginal delivery. His temperature is 36.7°C (98°F), pulse is 120/min, respirations are 40/min, and blood pressure is 85/60 mmHg. Physical examination shows low-set ears, micrognathia and clenched fingers. Abdominal examination shows a midline non-reducible mass covered by a whitish membrane. Which of the following is the most likely cause of this patient's abdominal findings?  

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Gastroschisis p. 366


Content Reviewers

With gastroschisis, gastro- refers to the gastrointestinal tract, and -schisis refers to separation; so in gastroschisis, the anterior abdominal wall fails to close and remains open or separated throughout fetal development, and this results in a newborn’s abdominal organs, often the intestines, protruding out and being exposed to the outside environment.

Now, during the fourth week of fetal development, the embryo starts to change shape from a flat, three-layer disc to something closer to a cylinder, called embryonic folding.

Looking at the embryo in the horizontal plane, the two lateral folds eventually come together and close off at the midline, except for one tiny spot where the umbilical cord connects the fetus to the placenta.

That opening later becomes the umbilicus, also known as the belly button.

This folding allows for the formation of the gut within the abdominal cavity.

With gastroschisis, those lateral folds don’t close all the way, essentially leaving an opening in the abdominal wall.

The hole almost always extends through the rectus muscle to the right of the umbilicus, although it’s not really known why it tends to be on the right side.

Whatever the reason is, this opening allows the developing organs to protrude through into the amniotic sac.

Exposing the abdominal organs to amniotic fluid can sometimes cause the intestines to get irritated and inflamed, which can lead to malabsorption issues.

Following delivery in gastroschisis, the bowels are exposed and they’re not covered by a peritoneal layer.


  1. "Robbins Basic Pathology" Elsevier (2017)
  2. "Harrison's Principles of Internal Medicine, Twentieth Edition (Vol.1 & Vol.2)" McGraw-Hill Education / Medical (2018)
  3. "Pathophysiology of Disease: An Introduction to Clinical Medicine 8E" McGraw-Hill Education / Medical (2018)
  4. "CURRENT Medical Diagnosis and Treatment 2020" McGraw-Hill Education / Medical (2019)
  5. "Gastroschisis: A State-of-the-Art Review" Children (2020)
  6. "Epidemiology, management and outcome of ultrashort bowel syndrome in infancy" Archives of Disease in Childhood - Fetal and Neonatal Edition (2017)

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