Down syndrome, the full name of Down syndrome, is a genetic mutation disease, which occurs when the baby is in the mother's belly, so it is also an incurable disease and can only be prevented. Most children with Down syndrome have serious mental problems, which can be seen from their faces. Because their eyes are wide apart, they often spit out their tongues and their teeth are not fully developed. Even some children with Down syndrome can't control their emotions and cry when they are slightly dissatisfied.

Dunn's children have a short life span, and the longest is about 50 years old, but they are also plagued by diseases. Due to the slow development of various organs, its height is also lower than that of ordinary people.

? How is Down's son formed? 1. Environmental impact

If the expectant mother accidentally touches some radiation, chemicals, drugs, etc. During pregnancy, it may lead to abnormal embryo differentiation. The first three months of pregnancy is an important period of embryo differentiation, so mothers should be especially careful.

2. The influence of age

With the growth of expectant mothers' age, their physical ability declines, and it is easier to give birth to children with Down syndrome. The probability of chromosome abnormality in elderly women is higher than that in young women. Studies have shown that the probability of pregnant women aged 20-29 giving birth to Down's children is1/5000; 30-34 years old is about1/900; 35-39 years old is about1/250; And over 45, it is as high as 1/40. Moreover, older women will increase the chances of dystocia, pregnancy-induced hypertension and diabetes.

3. Genetic influence

Many people say that Down's son can't be inherited, but in fact, in our real life, there are some families that have Down's son giving birth to Down's son, especially if Down's mother gives birth to Down's son, the probability of Down's son's father will be lower. That is to say, both parents in the family have chromosomal abnormalities, especially chromosome 2 1, and the probability of Down syndrome is very high.

How do you know if the fetus is down syndrome? 1. NT examination can be done after 3 months of pregnancy. It scans the transparent layer of the fetal neck by ultrasound. If the test result is greater than 3 mm, it means that the fetus has a high probability of Down syndrome. If the test result is less than 3mm, the fetus is healthy. However, NT examination is very time-sensitive, and it is not accurate to check it after a certain period of time, so it needs to be checked according to the time arranged by the doctor.

2. There is a Down's syndrome screening in the fourth month of pregnancy. By taking the blood of the pregnant mother, combined with her age, gestational age, menstrual period and weight, the probability of Down's syndrome is calculated. The inspection results are mainly high risk, critical point and low risk, and the high risk needs further inspection; Pay attention to the critical point, and pay more attention to the follow-up inspection; Low risk means low probability. However, the accuracy of Down's screening is only about 80%. If there is a high risk, don't worry too much, because it is affected by age, weight and menstrual cycle, and the accuracy is also affected.

In short: in order to avoid the birth of Down's baby, we must pay attention to prenatal examination!