What are the chances that my baby has an abnormality?
Unfortunately, congenital abnormalities affecting babies' health are common. About 3% of all babies have some sort of physical or mental abnormality or limitation.
Chromosome abnormalities, such as Down syndrome or Trisomy 18, are most often related to the age of the mother. To figure out the chances that your baby might have Down syndrome or Trisomy 18, please enter your age in the box below. A table will then appear showing you the chances that your baby might have such a problem. The table will also show you the chances of these problems for women of other ages so that you can see how your risk compares with others.
Calculate your risk of Down syndrome
Cardiac abnormalities, such as "hole in the heart", occur in approximately eight in every 1,000 pregnancies (slightly less than 1%). Fortunately, many of these heart abnormalities are minor and do not require paediatric surgery. Some however are so serious that it may be necessary for your doctor to make special arrangements about where you deliver, and for your baby to undergo urgent heart surgery. If you have previously had a baby with a heart problem, or if someone in your family or your partner's family have had a baby with a heart problem, your chances of this happening may be significantly higher. In this situation, you should bring this to the attention of your doctor for further specific advice.
Spine and brain abnormalities, such as spina bifida, occur in approximately two in every 1,000 pregnancies. Unfortunately, these problems seem to be more common in Ireland compared to other countries. If you take folic acid supplementation prior to becoming pregnant, and during the first two months of pregnancy, your chances of these problems should be significantly lower. If you have previously had a baby with such a spine problem, or if someone in your family or your partner's family have had a baby with a spine problem your chances of this happening may be significantly higher. In this situation you should bring this to the attention of your doctor for further specific advice.
Genetic abnormalities, such as cystic fibrosis, can occur even without any family history in your or your partner's backgrounds. However, in some cases both you and your partner may be carrying an abnormal gene without it affecting either of you. If both of you happen to pass on that abnormal gene to your baby, then your baby may have as high as a one in four chance of having a serious disease. For example, about one in every 20 Irish people carries an abnormal gene for cystic fibrosis. It is difficult to provide you with specific risk information for the many genetic abnormalities without first performing a detailed review of three generations of your and your partner's family background. This should be arranged through your doctor with a genetic counsellor if there is a specific concern.
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