These are some of the conditions which are commonly associated with antenatal testing; there are other rarer conditions which can be picked up as well.
Down's Syndrome This is a 'chromosomal abnormality' which means that there is something wrong with one of the genes which the baby inherited from his parents.
It is the most common cause of severe mental disability in the UK.
About 1,000 babies who have Down's syndrome are born each year.
Edward's Syndrome This is also a chromosomal abnormality.
Babies born with Edward's syndrome have small heads and often have a cleft palate.
Their hearts and digestive systems are generally not properly formed.
Most die in the first year of their lives.
Turner's Syndrome All children born with Turner's syndrome are girls.
They have a distinctive appearance, a little like a Down's baby, but are generally not mentally disabled.
They tend to have heart problems and their reproductive organs do not develop properly.
Spina Bifida This condition means that the vertebra of the baby's spine do not properly protect his spinal cord.
Spina bifida can be very serious so that the person affected is paralysed and incontinent, or it may be much less serious and cause the person no problems at all during his life.
Anencephaly The baby's brain and skull have not developed properly which means that the baby can only live for a few minutes or hours after his birth.
Cleft Lip and/or Palate In the uterus, the baby's mouth develops in two parts which then join together.
Sometimes, the parts do not join and the baby is born with a hole in his lip and/or the roof of his mouth.
Surgery for these conditions is now excellent and cleft lips are treated as early as 3-4 months of age with cleft palates being closed during the second year of the baby's life.
Down's Syndrome This is a 'chromosomal abnormality' which means that there is something wrong with one of the genes which the baby inherited from his parents.
It is the most common cause of severe mental disability in the UK.
About 1,000 babies who have Down's syndrome are born each year.
Edward's Syndrome This is also a chromosomal abnormality.
Babies born with Edward's syndrome have small heads and often have a cleft palate.
Their hearts and digestive systems are generally not properly formed.
Most die in the first year of their lives.
Turner's Syndrome All children born with Turner's syndrome are girls.
They have a distinctive appearance, a little like a Down's baby, but are generally not mentally disabled.
They tend to have heart problems and their reproductive organs do not develop properly.
Spina Bifida This condition means that the vertebra of the baby's spine do not properly protect his spinal cord.
Spina bifida can be very serious so that the person affected is paralysed and incontinent, or it may be much less serious and cause the person no problems at all during his life.
Anencephaly The baby's brain and skull have not developed properly which means that the baby can only live for a few minutes or hours after his birth.
Cleft Lip and/or Palate In the uterus, the baby's mouth develops in two parts which then join together.
Sometimes, the parts do not join and the baby is born with a hole in his lip and/or the roof of his mouth.
Surgery for these conditions is now excellent and cleft lips are treated as early as 3-4 months of age with cleft palates being closed during the second year of the baby's life.