Now a new blood tests is ready to be used in clinics, this blood test can be implemented on pregnant women who have high risk of giving birth to a child with Down syndrome, the great thing about this test is that it’s safe as it can be done by taking blood sample to check the DNA, that’s why it can be used instead of the risky diagnostic procedures needed to identify the existence of the syndrome, this test can be done early in first part of pregnancy as the blood samples can be taken in the 10th week of pregnancy, especially to those women who are in high risk of the disease.
A large study was made to check this test, as it has been done on 1700 pregnant women who are in high risk of the chromosomal abnormalities, and 212 among them were affected by the Down syndrome.
This research was supervised and led by several doctors from several universities from San Diego, and Los Angeles, the results of this test are considered successful as it could identify 98.6% of the Down syndrome in pregnant women, also it showed a very small percentage 0.8%of failure in providing a clinical interpretation.
According to these good successful results on large number of samples, this test will be effective in case of women who are considering invasive testing.
And a doctor who participated in the study said that , if this test can be used in the method they described, then women who show fine and normal pregnancy can avoid an invasive diagnostic procedure and all its related problems such anxiety and cost, also the probability of fetal loss.
The Down syndrome is considered a dangerous disease as it is a disorder that usually occur in chromosomes with symptoms like mental retardation, characteristic facial features, and, often, heart defects, and the bad news is that affects 550 babies born each year in the US, which is considered large number relatively.
The reason behind this syndrome is having three copies of chromosome number 21in each cell in an individual, rather than having usual two copies which is considered normal, to undergo this test some information are required such as age of the mother, information from the measurement of maternal serum markers and ultrasound markers in the first and second trimesters of pregnancy.
This test is successful to detect 90% of Down syndrome while, have wrong diagnosing percentage of 2-5% but researcher as now working to reduce this wrong ratio.