Prenatal screening for Down syndrome

Every happy and complete family has children. A family without children is incomplete. Every young couple who gets married and has children, when they reach a certain stage and have a stable career and income, will want a cute baby. Everyone wants their children to be healthy. Before giving birth, pregnant women will undergo many tests to ensure the health of their babies, including prenatal screening for Down syndrome.

Every baby is born with the expectation of parents and many relatives. Every pregnant woman is very cautious before giving birth and has to do many tests to determine the baby's gender and whether the baby is healthy. Down syndrome is also known as congenital idiocy. Once a baby suffers from this disease, it will bring shadows to the family. Prenatal screening for Down syndrome is necessary.

Down syndrome is also called trisomy 21 syndrome, congenital idiocy. It means that the patient's 21st pair of chromosomes has one more than the normal person (normal people have one pair). It is the most common chromosomal aneuploidy disease. Down syndrome screening is performed at a specific gestational week by testing the levels of PAPPA, AFP, HCG, uE3 and Inhibin A in the pregnant woman's serum, combined with clinical information such as the pregnant woman's age, gestational age, weight, smoking status, and insulin-dependent diabetes, and the risk value is calculated using risk assessment software.

The critical value is 1250-380 (this value may vary due to different methodologies). Greater than is high risk, less than is low risk. The probability of having Down syndrome (DS) in the general population (under 35 years old) is 1 in 750. According to the examination time, it is divided into early pregnancy (9-13 weeks) and mid-pregnancy (14-21 weeks).

Down syndrome screening test is the abbreviation of prenatal screening test for Down syndrome. The purpose is to comprehensively judge the risk of the fetus suffering from Down syndrome by testing the pregnant woman's blood and combining it with other clinical information. If the Down screening test results show that the fetus is at a higher risk of suffering from Down syndrome, further confirmatory tests should be carried out - amniocentesis or chorionic villus sampling.

Inspection Principles

Through economical, simple and non-invasive testing methods, pregnant women at high risk of carrying certain congenital defects can be identified so that further diagnosis can be made and the birth rate of abnormal fetuses can be minimized. Prenatal screening usually refers to the detection of high-risk pregnant women carrying a fetus with congenital defects through the detection of maternal serum markers.

There are two periods for Down syndrome screening: the 9th to 13th week of pregnancy, which is called early pregnancy screening, and the 14th to 21st week + 6 days of pregnancy, which is called mid-pregnancy screening. Regardless of whether it is in the early or middle stages, pregnant women can generally get the screening results within a week after the blood test. If the result is high risk, there is no need to panic, because further chorionic villus sampling (early stage) or amniocentesis (mid-stage) will be required to perform fetal chromosome karyotype analysis to confirm the diagnosis.

If there is a family history of genetic diseases or other diseases, pregnant women must undergo prenatal examinations to ensure the health of the baby. Down syndrome prenatal screening is a prenatal diagnosis to confirm whether the baby has Down syndrome. If a family welcomes such a patient, their happiness will be greatly reduced, so pregnant women are advised to have a prenatal check-up to ensure the baby's health.