Congenital Diaphragmatic Hernia (CDH) occurs when the baby’s diaphragm does not form properly in the womb. The diaphragm is a muscle that helps with breathing and separates the heart and lungs in the chest from the bowel and other organs in the abdomen. With CDH, some of the baby’s abdominal organs, such as the bowel and liver, go through a hole in the diaphragm at about 10 to 12 weeks into the pregnancy and take up space in the chest where the lungs should be growing. CDH occurs on either side, but much more commonly on the left.
CDH occurs in about 1 in every 3,000 babies and accounts for 8% of all major birth defects. Up to
20% of babies with CDH also have a chromosomal abnormality such as Down’s or Edward’s syndrome.
Duodenal atresia is a condition where the first part of the duodenum has not developed properly and is closed rather than being a tube so that the stomach contents cannot pass into the intestine. Surgery will be required to repair the duodenum. This condition has an incidence of around 1 in 6000 live births and around 50-66% are identified antenatally. There is an associated chance of Down’s Syndrome (around 33%), oesophageal atresia (7-10%) and cardiac anomalies (around 40%).
Exomphalos (Omphalocele) is a weakness of the baby’s abdominal wall where the umbilical cord joins it. This weakness allows the abdominal contents, mainly the intestines and the liver to protrude outside the abdominal cavity where they are contained in a loose sac that surrounds the umbilical cord. As the contents are lying outside it, the abdominal cavity often does not develop properly and remains small in size. The cause of this condition is unknown and is a rare problem occurring in about 1 in 4000 pregnancies.
About half of all babies with Exomphalos will have problems affecting other body systems. Most commonly affected are the heart as well as chromosome abnormalities. Following delivery, intravenous fluids provide nourishment until surgery can proceed. Type of surgery will depend on size of Exomphalos. The majority of these cases will be diagnosed antenatally.
Gastroschisis is a birth defect of the abdominal wall. The baby’s intestines are found outside of the baby’s body, exiting through a hole beside the belly button. The hole can be small or large and sometimes other organs, such as the stomach and liver, can also be found outside of the baby’s body. Following delivery, intravenous fluids will provide nourishment and treatment will begin to replace the baby’s organs back into the abdomen with surgery often required depending on the severity of the condition.
Gastroschisis has similar incidence to Congenital Diaphragmatic Hernia, around 1 in 2000 births, and is mainly diagnosed antenatally with most identified pregnancies surviving to term. This means an expected national number of around 20-25 newborns per year in Scotland.
Oesophageal Atresia is a birth defect in which the oesophagus is segmented and closed off at any point. This condition usually occurs with tracheoesophageal fistula, a condition in which the oesophagus is improperly attached to the trachea. Surgery will be required to repair the oesophagus. Incidence is around 1 in 3000-4000 live births with an expected birth incidence of around 15 per year. Only a minority are diagnosed antenatally.