Have made the decision to go ahead with TRISOMY test? If you have, then you must know that it is a non-invasive prenatal screening test based on a sample of blood that can detect frequent fetal chromosome disorders. The next thing you most probably want to know now is when your test results will be ready and who will explain them to you. Read on to find out more.
WHEN WILL MY TEST RESULTS BE READY?
If you do not hesitate with the necessary payment, the laboratory will be able to start analysing the blood sample and prepare your results promptly. As a rule, this takes up to 5 working days. However, test results are only delivered upon completion of the 12th week of pregnancy (following a resolution adopted by the Ministry of Health of the Slovak Republic).
IS IT POSSIBLE THAT THE WAIT FOR THE RESULT WILL BE LONGER?
In about 10% of all cases, the waiting time may be prolonged from 5 to 8 working days. This usually happens when a blood sample cannot be processed in accordance with the principles of good laboratory practice (the laboratory is not able to obtain the desired quality of biological material for analysis). In such circumstances, we repeat the analytical procedure based on the same blood sample (although no extra payment is required, the period for the delivery of test results will be prolonged from 5 to 8 days). In most cases, repeated analysis will yield informative results.
Should the repeated analysis not yield informative findings, or the blood sample does not contain a sufficient amount of fetal DNA (this occurs in about 3% of all cases), another blood sample has to be taken in 14 working days. Indispensable for this kind of analysis, the proportion of fetal DNA in maternal blood gets progressively higher further on in pregnancy, which is why 2 out of 3 repeated tests based on new blood samples actually yield informative results.
Statistically speaking, about 4% of all women in the population have a proportion of fetal DNA in their blood that is actually insufficient for the kind of DNA analysis used in non-invasive prenatal tests (NIPTs). For these women, NIPTs or other similar tests are not suitable.
WHAT KIND OF RESULTS CAN BE EXPECTED?
|Negative results||Trisomy of chromosome 21, 18 or 13 not detected.||A screen-negative result does not have to be validated by another test; the patient’s attending physician, usually a gynaecologist, will choose further healthcare to be provided.|
|Positive results||Trisomy detected in one of the examined chromosomes.||A screen-positive TRISOMY test result must be confirmed by a genetic test based on a sample obtained using invasive sampling. It is vital that the patient consults her results at a clinic specialising in medical genetics.|
|Non-informative results||The sample provided could not be processed in accordance with the principles of good laboratory practice or the result of the screening test does not answer the diagnostic question even if the sample is repeatedly analysed.||Another blood sample must be taken (no additional payment is required), usually 14 days later. The concentration of fetal DNA in maternal blood gets progressively higher further on in pregnancy.|
WHO WILL TELL ME THE RESULTS?
Test results can only be provided to the patient via the doctor who referred them for the screening test. The laboratory cannot provide any test results directly to the pregnant woman (respecting the doctor’s position as a health care provider).
The laboratory only notifies the pregnant woman of the fact that her blood sample has been analysed. If this happens, it means that one of the results specified above has been sent to the doctor who referred the patient for the test. The test results will subsequently be disclosed to the patient by her doctor in a way that the two of them agree on.
For more details on the TRISOMY test screening procedure, and to read opinions provided by physicians and pregnant women, go to www.trisomyhu.wpengine.com.