For most mums-to-be, the first scan will be a dating scan at between 10 weeks and 13 weeks plus six days of pregnancy. However, the timing of your first scan will also depend on how your pregnancy is going, and where you live.Your midwife may recommend an early scan at between six weeks and 10 weeks if you have experienced bleeding, pain, or problems in a previous pregnancy.Use of multiple parameters orcombined testhelped to significantly increase detection rates.
A nuchal scan or nuchal translucency (NT) scan/procedure is a sonographic prenatal screening scan (ultrasound) to detect cardiovascular abnormalities in a fetus, though altered extracellular matrix composition and limited lymphatic drainage can also be detected.
Since chromosomal abnormalities can result in impaired cardiovasular development, a nuchal translucency scan is used as a screening, rather than diagnostic, tool for conditions such as Down syndrome. The scan is carried out at 11–13 6 weeks pregnancy and assesses the quantity of fluid collecting within the nape of the fetal neck.
When you book online, depending on your chosen location you may be contacted to arrange the most convenient way for you to have this done close by.
Your blood test results, nuchal thickness measurement and other maternal information are combined to determine your individual risk factor with 90-95% accuracy.
The first method of screening for Down syndrome introduced in the 1970s was the use of maternal age.
Any woman above the age of 35 was offered amniocentesis.
Until recently, the only reliable ways to determine if the fetus has a chromosomal abnormality was to have an invasive test such as amniocentesis or chorionic villus sampling, but such tests carry a risk of causing a miscarriage estimated variously as ranging between 1% Most women, especially those with a low risk of having a child with Down syndrome, may wish to avoid the risk to the fetus and the discomfort of invasive testing.
In 2011, Sequenom announced the launch of Materni T21, a non-invasive blood test with a high level of accuracy in detecting Down syndrome (and a handful of other chromosomal abnormalities).
A large number of women underwent amniocentesis and 70% of Down syndrome babies that were born to younger women were missed.