Why is the Nasal Bone Important at the 12 Week or Dating Scan?
One of the things that your sonographer may mention at your 12 week scan is the baby’s nasal bone. Being told that the bone is not visible can be worrying, but you might wonder why so much importance is placed on the presence of this one tiny bone.
Checking for the Nasal Bone
The nasal bone check forms a key part of the medical tests performed during the scan that you have at around 12 weeks. The nasal bones are the two small bones that jut out from the skull at the top or bridge of the nose. The doctor or sonographer will simply check to see if the nasal bones are visible. In most cases, they can be seen clearly on the scan. However, if they can’t then it can be a sign that your baby might have a chromosomal condition such as Down’s syndrome.
What Happens if the Nasal Bone Can’t Be Seen?
The presence or absence of a nasal bone on the scan will help your sonographer to assess the probability of Down’s syndrome and other chromosomal abnormalities. However, it is not enough to determine the probability by itself and cannot be used to diagnose any conditions. Other information collected during the scan, such as the size of the nuchal fold, will also be used to determine the probability. If your baby is determined to be at higher probability, you will have a chance to discuss the results with a consultant. The doctor may recommend further screening through NIPT
or a diagnostic test such as amniocentesis. If the nasal bone is not visible, but everything else appears normal then it can also be a good idea to schedule another scan in a week’s time as the nasal bone may be visible then. Whatever happens during your scans, you will always get the support and advice that you need at The Birth Company.