Is it accurate to do Down syndrome screening at 16 weeks?

Down syndrome screening is a very important screening project for pregnant women. Pregnant women need to do it. It can be done in the second trimester. Many expectant mothers want to know whether the baby in their belly is healthy. Generally, it can be checked through Down syndrome screening. So, is Down syndrome screening at 16 weeks accurate?

Is Down syndrome screening accurate at 16 weeks?

Down syndrome screening is a test method that extracts blood cells from pregnant women, tests the concentrations of alpha-fetoprotein, human gonadotropin and free estriol in the mother's blood cells, and calculates the risk of giving birth to a fetus with congenital defects based on the pregnant woman's date of delivery, weight, age and weeks of gestation when blood is drawn.

1. Down syndrome screening is a possible related examination: the focus is only on the fetus being more likely to be a Down syndrome baby, and there is also the possibility of Down syndrome in the low-risk group

2. About 1/10 of all pregnant women are key targets for screening, and 1-2/100 of the key targets are Down syndrome babies, that is, 1-2/1000 of pregnant women are Down syndrome babies.

3. When the blood test screening value exceeds 1/270, it is a key target, and the standard value is around 1/700. The international standard is 1/270

4. Down syndrome screening values ​​are adjusted values. The factors that affect the Down syndrome screening value mainly include: pregnant woman’s age, weight, weeks of pregnancy, fetal fetal protein secreted by the fetus, human chorionic growth hormone secreted by the embryo, drug factors, genetic factors, etc. Taking "Dolly Mama" during pregnancy may cause the human chorionic growth hormone to exceed the standard value and may affect the Down syndrome screening value.

Down syndrome screening test items

Down syndrome screening is a test method that extracts blood cells from pregnant women, tests the concentration of alpha-fetoprotein and human gonadotropin in the mother's blood cells, and calculates the risk of having a child with Down syndrome based on the pregnant woman's due date, age, weight and weeks of gestation when the blood is drawn. The purpose of Down screening is to identify the risk of the fetus having Down syndrome by testing the pregnant woman's blood. If the Down screening data shows that the fetus has a high risk of Down syndrome, further diagnostic tests should be carried out - amniocentesis or chorionic villus sampling.

Physical examination: weight, height, blood pressure, thyroid cyst, breast, chest and abdominal examination, pelvic examination, TCT examination. Blood tests were performed to check for high alpha-fetoprotein, syphilis, HIV, hepatitis C, six items of hepatitis B, kidney function, blood sugar, and hepatitis A antibodies. Check on an empty stomach, bring some food with you, it is best not to eat in the morning, eat something after the check

Down syndrome screening involves drawing blood cells from pregnant women to test the concentrations of alpha-fetoprotein, gonadotropin, and free estriol in the blood cells. The risk factor of Down syndrome is calculated by combining the date of birth, weight, age, and the number of weeks of pregnancy when the blood was drawn. This method can detect 80% of Down syndrome babies.