How many weeks should Down syndrome screening be done?

In the past, due to different social divisions of labor and role-playing, many female friends had already taken care of their husbands and children at a very young age. However, with the progress and development of society, women have gradually stepped out of their families and participated in the construction of society. As a result, the age at which women give birth is also being pushed back, and even many older mothers have appeared. Down syndrome screening is an examination item during prenatal checkups for pregnant women. High-risk groups such as older pregnant women must undergo such an examination. So, how many weeks is the best time to do Down syndrome screening?

1. Screening for Down syndrome in the first trimester

This examination is mainly performed when the pregnant mother is between 10th and 13th + 6th weeks of pregnancy, using two screening methods: "ultrasound" and "blood test". Dr. Huang Xuguang said that through ultrasound, the thickness of the fetal nuchal translucency can be clearly measured, and combined with blood tests, the plasma protein A value and human chorionic gonadotropin value in the mother's serum can be measured to estimate the risk of the fetus suffering from Down syndrome.

2Second trimester Down syndrome screening

Pregnant mothers will have their blood drawn between the 15th and 20th weeks of pregnancy. The hospital will test the levels of alpha-fetoprotein, human chorionic gonadotropin, free estriol and inhibin in the serum, and then calculate the risk of the fetus suffering from Down syndrome based on the mother's age, weeks of pregnancy and weight.

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 the early or middle stage, pregnant women can usually get the screening results within a week after the blood test.

Time: Early pregnancy: 9-13 weeks, mid-pregnancy: 14 weeks to 21 weeks + 6 days, preferably between 16 and 18 weeks.

From the above introduction, we can understand that the best time to conduct Down syndrome screening is between 16 and 18 weeks. Down syndrome screening is the basis for determining whether the fetus in the pregnant woman's womb suffers from congenital idiocy and other symptoms, and it can also understand the development status of the fetus. Although the accuracy of Down syndrome screening is not as good as amniocentesis, it is also very important for understanding the condition of pregnant women and fetuses. I hope all expectant mothers and babies are healthy.