Causes of high risk of trisomy 21

This Down syndrome screening is a small test that every pregnant woman hopes to pass. After all, no one wants to be a Down syndrome pregnant woman, right? Some people still have to undergo amniocentesis surgery when the baby is 1 month old because they fail the Down syndrome screening. This is very dangerous. So what are the reasons for the high risk of trisomy 21? Let's discuss it.

Causes of high risk of trisomy 21:

Generally, genetic inheritance is relatively large, and it is not ruled out that chromosomal abnormalities may be caused by exposure to chemicals in the middle and late stages. The high risk of trisomy 21 is just a matter of probability. Even if you do amniocentesis or minimally invasive surgery, it is divided into high risk and low risk. There is no precise answer. Don't worry too much, most of the minimally invasive surgeries or amniocentesis that are considered high-risk are now low-risk. The reason for the high risk of trisomy 21 is that it is closely related to the sex chromosomes, that is, genetic level, of you and your husband. It is congenital. The treatment first requires an amniocentesis. After that, the chance of trisomy 21 occurring in the newborn will not be very high.

What should I do if I have a high risk of trisomy 21?

The adverse effect of Down syndrome with a higher risk is congenital intellectual disability in the fetus, which is directly related to genetic inheritance and maintenance during pregnancy. As long as there is no problem in the family and the baby develops normally, there is no problem. The risk level varies according to the age and physical fitness of the pregnant woman. The probability of occurrence is extremely low, so there is no need to worry. The best time is between 14 and 21 weeks of pregnancy. It is recommended that pregnant women with a history of Down syndrome and older pregnant women must go for prenatal check-ups to avoid missing the best time. At present, there is also a non-invasive method to diagnose Down syndrome, called minimally invasive fetal sex chromosome aneuploidy testing or minimally invasive DNA testing. But it is not as accurate as amniocentesis.

What is Down syndrome screening?

Down syndrome screening is an examination item in the second half of pregnancy. It is mainly based on extracting blood cells from pregnant women, testing the concentration of alpha-fetoprotein (AFP) and human chorionic gonadotropin (β-hCG) in the blood, and combining the date of birth, age, weight and the number of weeks of pregnancy when blood was drawn to calculate the risk of having a child with Down syndrome.

Down syndrome screening is a testing method with special practical significance. It is aimed at special groups that have no corresponding disease signs (such as all pregnant women). Through the test, key subjects who are most likely to suffer from a certain disease can be selected for subsequent diagnosis-related examinations. One thing that needs to be established is that the purpose of screening is not to diagnose a certain disease, but to select people who are very likely to have a certain disease.

When should Down syndrome screening be done?

Pregnant mothers must grasp the right time for Down syndrome screening, because whether it is early or late, it will affect the accuracy of the test results. If you miss the time range, you will not be able to make up for the examination and can only do amniocentesis. It is best to do Down syndrome screening between 15 and 20 weeks of pregnancy.

Advance preparation before Down syndrome screening:

There is no need to fast for Down syndrome screening, but if the pregnant mother needs to have blood tests and other tests in addition to Down syndrome screening, the doctor may require fasting, so it is best for the pregnant mother to consult the doctor for other preparations before the test. You must choose the right time for Down syndrome screening, otherwise you will not be able to make up for it if you miss it. Therefore, you must prepare in advance and consult a doctor immediately if you have any questions.