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.
The baby will be measured, and the anatomy examined in detail.
The top line represents the skin and bottom one, represents the nasal bone.
A third line, almost in continuity with the skin, but at a higher level, represents the tip of the nose.
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 test cannot be performed outside this time frame as certain features that need to be seen on the scan are not present.
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.
The fluid collection is however increased in many fetuses with Down's syndrome and many other chromosomal abnormalities.
It is called a 'translucency' because on ultrasound this appears as a black space beneath the fetal skin.
You do not need to have a full bladder, a moderately filled bladder is needed for a proper examination.