If a scan has shown that your baby has a diaphragmatic hernia one of the doctors will have explained this to you and this page aims to give you basic information about the condition. If you would like to discuss things further we can arrange for you to talk to our paediatric surgeon and his liaison paediatric nurse.
This condition is a hole in the diaphragm (the thin muscle which separates the heart and lungs from the other contents of the abdomen) which allows the intestines, stomach or liver to move up into the chest, next to developing lungs of the fetus. The lungs and heart normally occupy the whole of the chest and the presence of the hernia can sometimes mean that there is not enough room for them to develop normally.
Relatively common, about one in every 2,000 babies is born with a diaphragmatic hernia.
Diaphragmatic hernia usually happens 'out the blue'. It is not due to a defect in either of the parents or because the mother has 'done something wrong' during or before the pregnancy. Very rarely it is genetic condition.
This is extremely unlikely: the chances are usually no greater than those of any other couple (1 in 2,000).
Approximately 30 out of 100 cases of diaphragmatic hernia are due to the presence of a chromosomal abnormality such as Edwards's syndrome (Trisomy 18).
A detailed ultrasound scan will look for features of chromosomal abnormality but it may also be necessary to take a sample of blood from the fetus (by cordocentesis). This test will confirm or exclude a chromosomal abnormality. Cordocentesis carries a small risk of miscarriage (about 1%).
Often a diaphragmatic hernia is an associated with polyhydramnios (excess amniotic fluid around the baby). During the pregnancy the fetus is constantly drinking amniotic fluid. If the diaphragmatic hernia is pressing against the tube from the baby's mouth (the oesophagus) the baby will not be able to drink properly and so the amount of fluid builds up; we can assess this during the ultrasound scan. If there is a lot of extra fluid, you will notice that your womb feels very swollen. It may be necessary to drain this fluid to prevent premature labour and inserting a fine needle into the womb and draining the excess fluid can do this. The procedure carries a small risk of miscarriage (about 1%). Provided that the chromosomes are normal and there are no other abnormalities detected by the scan, further treatment for the diaphragmatic hernia can be carried out after the baby is born.
This depends entirely on how much the lungs have developed before birth. Sometimes, if the hernia is severe, there is simply not enough room for the lungs to develop (pulmonary hyperplasia). If there is very little lung tissue present at birth, or if the lung has been so compressed that the baby has not been able to ' practice breathing', it may not possible for the baby to breathe even with the aid of artificial ventilation. About 50% of babies with a diaphragmatic hernia will die shortly after birth. If the hernia is only mild or moderate and the only problem, then the lungs can normally develop. The babies will normally need some help with breathing when they are first born; they will usually survive and do well.
At birth the baby will need to be taken straight to the special baby care unit, to be given help with breathing. The baby will need to remain on the unit until the lungs have developed sufficiently for the baby to breathe normally. The baby will be put on a ventilator and a small tube will be passed down the stomach to prevent the baby from swallowing air and putting further pressure on the lungs. The baby will also be given some drugs to prevent heart failure as the cardiovascular system will have been compromised by the presence of the diaphragmatic hernia.
The baby will need as operation to put the intestines back into the abdomen and close the hole in the diaphragm. This operation will be performed within 48 hours of the baby's birth.
You will be offered regular scans throughout your pregnancy to monitor the development of the lungs and the amount of amniotic fluid present. If the diaphragmatic hernia is severe and the outlook seems poor you may decide to have a termination of pregnancy, in this case we can also put you touch with specialist support groups such as SAFTA.