Is fasting required for early Down syndrome screening?

After pregnancy, you need to do a lot of regular examinations. The examinations needed at different stages of pregnancy are also different. Down syndrome screening is a must-do examination during pregnancy. This examination is very important. It is used to screen whether the fetus is mentally retarded. If the test result is high risk, further examinations are usually required. If it is confirmed to be mentally retarded, the pregnancy needs to be terminated as soon as possible.

Is fasting required for early Down syndrome screening?

Fasting is not required for Down syndrome screening. Although Down syndrome screening is done through blood drawing, it is mainly to check whether the fetus has any deformities, which is different from blood drawing for liver function tests and other items. Therefore, there is no requirement for fasting for Down syndrome screening.

Down syndrome screening requires drawing a tube of venous blood from the pregnant mother. The risk factor of giving birth to a child with Down syndrome is calculated by testing the concentration of alpha-fetoprotein (AFP) and human chorionic gonadotropin (hCG) in the maternal serum and combining the pregnant woman's due date, age, weight and gestational age at the time of blood collection. Pregnant mothers can usually get the test results one week after the blood is drawn.

When doing Down syndrome screening, the following information must be accurately provided: the pregnant woman's date of birth, menstrual cycle, last menstrual period, expected date of delivery, number of fetuses, weight, and actual gestational age (the expected date of delivery must be checked. For example, a pregnant woman's menstruation is usually delayed by two weeks, and according to the last menstrual period, she is 18 weeks pregnant. However, due to the characteristics of delayed menstruation, the early pregnancy ultrasound result is two weeks smaller, and the actual gestational age is only 16 weeks).

The timing of Down syndrome screening is also very important. Usually, the Down syndrome screening we call is conducted in the second trimester, but in recent years it can also be conducted in the early pregnancy. The time for Down syndrome screening in early pregnancy is 11 to 14 weeks, and the best time is 11 to 12 weeks. The main purpose of Down syndrome screening is to avoid the risk of congenital idiocy in the fetus to a certain extent.

Doctors recommend that the time for mid-pregnancy Down syndrome screening is between 15 and 20 weeks of pregnancy, and the best time to check is between 16 and 18 weeks. Because whether it is early or late, it will affect the accuracy of Down syndrome screening results. If the hospital report determines that the situation is high-risk during the screening process, the doctor will generally recommend amniocentesis. If a pregnant woman misses the time period for Down syndrome screening, she cannot make up for it and can only undergo amniocentesis to test for Down syndrome by drawing amniotic fluid.