Do pregnant women need to fast for non-invasive surgery?

At present, the prenatal examination programs in hospital outpatient clinics are becoming more and more excellent, and the options for pregnant women are becoming more and more diverse. Some prenatal examination items must be checked, such as blood pressure, uterine height, fetal abdominal circumference, B-ultrasound, etc. Some are optional, such as four-dimensional color ultrasound, Down syndrome screening, minimally invasive DNA, etc. So, do you need to fast for non-invasive DNA testing?

Do I need to fast for non-invasive DNA testing?

No need to be on an empty stomach.

There are various ways to test for chromosomal abnormalities in the growing fetus, including minimally invasive DNA prenatal testing, also known as minimally invasive prenatal DNA testing, minimally invasive fetal sex chromosome aneuploidy testing, etc. According to the American Association of Colleges of Obstetricians and Gynaecologists, an international authoritative academic research organization, minimally invasive prenatal DNA testing (Non-invasive Prenatal Testing) is the name of the most widely used technology. The minimally invasive DNA prenatal non-destructive testing technology only uses the pregnant woman's venous blood, and uses the next-generation DNA sequencing technology to sequence the mineralogic DNA fragments (including the fetal mineralogic DNA) in the pregnant woman's jugular venous blood. The sequencing results are then analyzed for biometric characteristics, from which the fetus's genetic material can be obtained, thereby testing whether the fetus suffers from the three major sex chromosome diseases.

The content of fetal DNA in the mother's jugular vein blood accounts for about 3-13% of all DNA, and different studies have shown that its content is slightly higher. Due to the influence of a large amount of mineral DNA from the mother's background, it is necessary to use very sophisticated new-generation biological technology to accurately identify the base sequence of the fetal mineral DNA at a high-information level. In early studies, minimally invasive prenatal DNA analysis for trisomy testing required multiple fetal DNA or RNA markers, which made the experiments very time-consuming and expensive[4]. The improved and enhanced technology is called massively parallel genome sequencing technology. It uses a highly sensitive detection method to quantify and analyze millions of DNA fragments. Compared with early technologies, it can accurately detect trisomy 13, trisomy 18 and trisomy 21 syndromes.

Clinical application of non-invasive DNA

As of 2012, this method can accurately detect the three major sex chromosome diseases: Down syndrome (T21), Edwards syndrome (T18), and Parkinson syndrome (T13). The non-traumatic nature of minimally invasive DNA prenatal testing can avoid the risks of miscarriage and infection caused by invasive diagnosis. The perfect features of DNA sequencing technology ensure the technical success rate. Pregnant women over 12 weeks can be tested and the test results can be obtained within 10 working days.

So far, there is no effective treatment for sex chromosome diseases. Therefore, the best way to reduce the risk of giving birth to a child with a sex chromosome disease is to conduct prenatal genetic counseling and prenatal testing, diagnosis, detection and treatment as soon as possible.

Internationally, the United States already has development and services for this technology, and companies that provide this technology include Sequenom and Natera. Moreover, in some areas (states), the cost of this test can be partially covered by commercial insurance, so it is very popular among pregnant women, especially older pregnant women. In Europe, at least LifeCodexx provides this service, but due to Europe's relative traditions in obstetric technology and beliefs, the advancement of this technology is relatively slow compared to the UK. It can be seen from overseas clinical research data that the diagnosis rate of minimally invasive DNA prenatal non-destructive testing technology for the three major sex chromosome diseases of the fetus (Down syndrome (T21), Edwards syndrome (T18), and Patau syndrome (T13)) is over 90%.