How does Edwards syndrome happen?

Children with Edwards syndrome have three copies of part or all of chromosome 18, instead of the usual two copies. It is also called Trisomy 18.

This can be caused by a mistake in the formation of the egg or sperm, or the problem can arise while the baby is developing in the womb.

Babies with Edwards syndrome are either miscarried, stillborn or born with severe physical abnormalities. It is very rare for a baby with Edwards syndrome to survive their first year of life, and most die within a week of birth.

Edwards syndrome is much more common in girls.

Symptoms and signs of Edwards syndrome

Most babies with Edwards syndrome have:

• feeding difficulties
• breathing difficulties
• intellectual disabilities
• abnormal growth and development
• undescended testes (in boys)

Some babies also have:

• an unusual-looking face and head
• unusual hands and feet with overlapping fingers and webbed toes
• small bones in the pelvis and chest
• problems with organs such as the heart, lungs and kidneys

Edwards syndrome diagnosis

Edwards syndrome can be suspected or even diagnosed during pregnancy.

Some parents find the possibility of Edwards syndrome is raised with them after a pregnancy ultrasound. It is also possible to have a screening test while pregnant – this is usually offered to women over 35 as the chances of having a baby with Edwards syndrome increase with the mother’s age.

But the only definite way to diagnose Edwards syndrome is through genetic testing. This can be done while the baby is in the womb using chorionic villus sampling (CVS) or amniocentesis. Both these tests have a risk of miscarriage. You can talk to your obstetrician or midwife about this.

Sometimes, Edwards syndrome is not suspected during pregnancy, and is only discovered when the baby is born.

Visit Pregnancy, Birth and Baby website for more information on prenatal screening.

Edwards syndrome treatment

There is no effective long-term treatment for babies with Edwards syndrome. Parents in this situation face a very hard choice. They can choose to try to keep their babies alive in the neonatal intensive care unit. Or they can choose to have their baby receive palliative care until he or she dies.

More information

Visit our genetic disorders guide to learn more about genes, types of genetic disorders and where to go for help and more information.