Nuchal scan accurate dating
If the nasal bone is visible at the scan then this will reduce the chance of your baby having Down's syndrome.The view of the nasal bone should show three distinct lines: The first two lines, are horizontal and parallel to each other, resembling an 'equal sign'.
This test results in a 9095% detection rate of pregnancies that may be at an increased risk of carrying a genetical problem such as Downs Syndrome.You will probably be give you a printout of your baby by the sonographer as a keepsake, it is important to remember the main purpose of the scan.The first Trimester Scan, is Scans are usually performed by a doctors, midwives or radiographers who are specially trained in ultrasound, and are known as sonographers. The amount of liquor (amniotic fluid), the position and appearance of the placenta and a detailed scan of the baby itself.It is this black space that you will see measured during the ultrasound scan.Currently the most accurate non invasive test for detecting Down syndrome during pregnancy is the measurement of the nuchal translucency with an ultrasound between 11 to 14 weeks of pregnancy.During the examination, the fetus is seen by abdominal ultrasound.
Occasionally the view is not clear and it may be necessary to perform a vaginal scan.
Crown Rump Length: Gestational age = 6 weeks plus (CRL x days).
For example, a CRL of 23 mm would correspond to a gestational age of 9 weeks and two days (6 weeks plus 23 days = 9 weeks and 2 days).
First trimester ultrasonic scans may show 'soft' markers for chromosomal abnormalities, such as an increased fetal nuchal translucency (back of the neck) to enable detection of Down's syndrome fetuses.
The test is performed between 11 weeks and 13 weeks 6 days into your pregnancy.
The fluid collection is however increased in many fetuses with Down's syndrome and many other chromosomal abnormalities.