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How to perform the G-test

By contacting our Institute, through the toll-free number 800 985 177, it is possible to receive all the preliminary information (timing, mode of execution, etc.) and the indications on the nearest partner centers to be contacted to perform the G-test.

Withdrawal and transport

The maternal peripheral blood sample required for the G-test is about 8ml; it can be performed starting from 10th week of gestation (within 24ᵃ) using the CE-IVD certified tube provided in the G-test collection and transport kit. The blood drawn is not entrusted to third parties or sent abroad.
The G-test is performed at the Bioscience Genomics laboratories, where the blood sample arrives inside an isothermal kit for the transport of biological material of category B, in compliance with the UN3373 standard.

Results management

Arrived at Bioscience Genomics, the blood sample is taken in charge by the laboratory biologists and the results are ready in about 7 working days. It should be noted that times may vary: the analysis includes a series of rigorous quality controls to ensure the reliability of the result; among these the verification of the quantity of fetal DNA present in the blood sample, which varies from pregnant to pregnant. In some cases, due to the low amount of fetal DNA, it is necessary to repeat the analysis and / or blood collection.

If it is necessary to repeat the test due to the low concentration of fetal DNA in the mother's blood, the repetition will be free. The results of the G-test for the evaluation of trisomies, as foreseen in the 2015 SIEOG Guidelines (Italian Society of Obstetric and Gynecological Ultrasound), are reported in terms of risk and not as presence / absence of anomaly. In the event of a "high risk" result it will be possible to ask for free genetic counseling and support for the execution of any diagnostic tests: if the high risk concerns the trisomies 13, 18 and 21, a contribution will be provided for the expenses. related to laboratory tests performed on chorionic villi or amniotic fluid.