Normal range of risk for trisomy 18

Everyone knows that pregnant mothers need to undergo Down syndrome screening. This is a necessary examination to prevent children with Down syndrome. It is also an assessment to ensure the current health status of the baby in the belly. During the Down syndrome screening process, some blood will be drawn from the pregnant mother and then tested. At the same time, there are many precautions to be aware of during the examination. Similarly, the normal value range of trisomy risk is also a concern for many mothers.

Cause Analysis

Down syndrome screening involves drawing blood from the pregnant mother and calculating the risk of having a child with Down syndrome based on alpha-fetoprotein, the mother's weight, blood sugar, age, etc. It is usually done between 14 and 20 weeks.

Precautions

1. Do prenatal check-ups on time to reduce the probability of fetal malformations;

2. Pay attention to folic acid supplementation to avoid fetal malformation;

3. Do appropriate exercise, eat a balanced diet, and pay attention to rest during pregnancy.

Secondly, after understanding the relevant knowledge about high-risk Down syndrome screening, pregnant mothers with high-risk Down syndrome screening can choose to do a non-invasive fetal free DNA test. The non-invasive fetal free DNA test involves drawing blood from the pregnant woman's vein, extracting and examining the baby's cells in the blood using a special instrument, and analyzing the chromosome structure and number of the chromosomes in the extracted baby's cells.

To determine whether there is trisomy 21, trisomy 18 or trisomy 13, and whether there are structural and numerical abnormalities in other chromosomes. If the non-invasive test shows low risk, then most babies are normal. Just have regular prenatal checkups. The accuracy of this screening is over 90%. If non-invasive testing indicates a high risk, prenatal diagnosis is needed.

Finally, prenatal diagnosis mainly includes chorionic villus sampling, amniocentesis, and umbilical cord blood puncture. These tests generally have the highest accuracy rates. If the Down syndrome screening or non-invasive test shows high risk, prenatal diagnosis is recommended to clarify the condition.