March 21, 2022 is
11th World Down Syndrome Day,
The active theme is
"Pay attention to Down's screening and give birth to healthy babies",
Aiming to raise awareness and attention to Down syndrome in the whole society,
Guide fertile women to take the initiative to undergo Down's screening after pregnancy,
Do a good job in pregnancy health care,
Science breeds healthy new life.
March 21 of each year is a special day for people with Down syndrome all over the world, and in December 2011, the United Nations General Assembly designated March 21 as "World Down Syndrome Day", and the 21st day was chosen because of the uniqueness of Down syndrome - the 21st pair of chromosomes has one more. Since 2012, an annual event has been held to give people with Down syndrome equal rights and dignity to the full and effective enjoyment of human rights and fundamental freedoms. There are currently more than one million "Tang babies" in the mainland, and the families of Tang babies are facing huge spiritual and economic pressures. The most important thing to scientifically reduce the incidence of Down syndrome is to focus on prevention, that is, to conduct Tang screening during pregnancy. This test is an important measure to reduce birth defects.
01 What is Down syndrome?
Down's Syndrome.DS, also known as Trisomy 21/Congenital Stupidity, is a congenital disease caused by the addition of one more chromosome 21, is the most common in humans, and is the first confirmed chromosomal disease in humans, mostly incidental, but also genetically. Down syndrome is one of the most common birth defects on the mainland. The disease was first described in 1866 by the British physician John Langdon Down, and later named it Down's syndrome after him, Chinese "Down syndrome".
02
What are the clinical manifestations of patients with Down syndrome?
Manifestations of the Down fetus under ultrasound:
NT, NF thickening, nasal bone deficiency or dysplasia, lateral ventricular widening, atrial septal defect, abdominal double vesicle sign, intestinal echo enhancement, etc.
The main clinical manifestations of Down's children:
1
Special facial signs;
Such as wide eye distance, low and flat nose root, small cleft, lateral oblique, with epicanthal folds, small external ears, fat tongue, often protruding out of the mouth, salivating. It is short stature, with a smaller head circumference than normal, a short anterior and posterior diameter of the head, and a flattened occipital head. The neck is short, the skin is loose, and the teething is delayed and often misaligned. The hair is fine and soft and less. The limbs are short, the phalanges are short, and the palm lines and grass shoes are common.
Mental retardation:
It is the most prominent and severe manifestation of Down syndrome. Its low intelligence gradually becomes obvious with age, with an IQ of 25 to 50, and motor development and sexual development are delayed.
3
Fertility:
Male Down babies grow up to adolescence and will not have fertility. Female Down babies grow up to have menstruation and are likely to have children.
4
other:
Children are often accompanied by congenital heart disease and other malformations, due to low immune function, susceptible to various infections, the incidence of leukemia is 10 to 30 times higher than the general. If you survive to adulthood, you often develop symptoms of senile dementia after the age of 30.
What causes Down syndrome to occur?
When many people hear about Down syndrome, they feel as if they have little to do with themselves. This is not the case, every healthy couple has the possibility of having a Down child, the incidence is random, which has nothing to do with education, status, etc. Although Down syndrome is a disease caused by genetic material (chromosomal) abnormalities, the vast majority of "Tang baby" parents are not also Down's patients, but some accidental error events lead to the formation of germ cells in the process of chromosome non-separation, so that chromosome 21 appeared three. A very small number of parents themselves are chromosomal balance translocation carriers with normal phenotypes, and the risk of disease when giving birth to the next generation will be greatly increased.
How to prevent Down Syndrome in the World?
Do a good job in the tertiary prevention of birth defects is an important means to prevent Down syndrome, scientific planning during pregnancy, screening for Down syndrome during pregnancy, finding high-risk groups through pregnancy screening, and recommending high-risk groups for prenatal diagnosis, early detection and timely termination of pregnancy, to avoid the birth of such children. Prenatal prophylaxis for pregnant women is as follows:
1. Genetic counseling
2. Prenatal screening and prenatal diagnosis
It is an effective measure to prevent the birth of children with Down syndrome. Couples with a history of fertility with a history of the disease should make a prenatal diagnosis, that is, karyotype analysis, including amniocentesis in the second trimester for amniotic fluid cells, embryonic villus cells in the second trimester, and umbilical cord blood lymphocytes in the second trimester.
05
How is Down screening done?
1. Down's screening
In the first trimester (9 weeks to 13+ 6) and the second trimester (15 weeks to 20 + 6), the concentration of alpha-fetoprotein and free chorionic gonadotropin (Free-βHCG) in the maternal serum was measured by drawing the peripheral blood of pregnant women, and combined with other information of pregnant women (including gestational age, weight, age, etc.), the detection method of down children's risk factors was calculated.
2. NT screening
Ultrasound screening of ultrasound indicators such as clear membrane thickness (NT), intravenous catheterization (DV), nasal bone (NB) and other ultrasound indicators in the first trimester of pregnancy (11 weeks to 13+ 6) of the fetus, the more obvious the NT thickening, the higher the chance of fetal abnormality, and the more serious the degree of abnormality.
3. Non-invasive DNA testing (NIPT)
Noninvasive DNA testing uses sequencing techniques to detect chromosomal abnormalities in the fetus by collecting free DNA from pregnant women's peripheral blood. Blood collection does not require an empty stomach and can be performed from 12 weeks of pregnancy. At present, the detection range can only detect the three most common chromosomal diseases, namely trisomy 21, trisomy 18, and trisomy 13.
4. Prenatal diagnosis
Amniocentesis is a prenatal diagnosis and is the gold standard for judging whether the fetus's chromosomes are abnormal, and it is recommended that all pregnant women at high risk of prenatal screening be used to diagnose whether the fetus is abnormal or not! Optimal testing time: 18 weeks to 22 weeks of pregnancy.
Prenatal diagnosis is required in the following populations:
(1) Pregnant women whose expected age ≥ 35 years old.
(2) Prenatal screening of high-risk groups (including NT examination, Down screening, non-invasive DNA test, these three types of screening of high-risk groups).
(3) Both husband and wife are carriers of single-gene diseases or pregnant women with a history of childbirth with single-gene diseases.
(4) A pregnant woman with chromosomal abnormalities or a child with a history of chromosomal abnormalities.
(5) Pregnant women who are suspected of having chromosomal diseases in prenatal examination (such as ultrasound examination showing fetal structural malformations, intrauterine growth and developmental delay, etc.).
(6) Pregnant women with a history of adverse pregnancy or contact with special teratogenic factors.
(7) Other doctors believe that there is a high degree of suspicion of fetal chromosomal abnormalities.
06
Frequently asked questions?
1. Is Tang Si's high risk determined to be pregnant with Tang's child?
The results of Down's screening are generally classified as high-risk, critical-risk, and low-risk. As a screening method, patients with high risk of Tang screening are not necessarily pregnant with Tang's children, but the risk is higher than that of ordinary people, and further examination is needed to confirm the diagnosis. In the same way, low risk can not rule out the possibility of Tang's children, but also need to be further ultrasonic investigation in the later stage.
2. Since it is non-invasive and accurate, why not do it directly?
Pregnant women peripheral blood fetal free DNA prenatal testing is also known as non-invasive prenatal testing, non-invasive detection rate of Down syndrome is about 98%, but there is still a possibility of missing tests, and the price is expensive, currently not as a first-line examination, only recommended Tang screening critical risk of pregnant women for examination, after consultation with doctors, pregnant women can consider their own situation to choose. Noninvasive testing is low risk and requires further testing in conjunction with ultrasound later.
3. Is it necessary to do Down's screening when the age < 35 years old?
Down's screening is for all pregnant women of appropriate age, and its convenience, speed and low price are suitable for promotion as a screening program among pregnant women of appropriate age. However, pregnant women aged ≥ 35 years of age have an increased risk of fetal chromosomal abnormalities, and even if the risk of Tang screening is low, the risk of advanced age, an independent risk factor, cannot be excluded, and interventional prenatal diagnosis is required.
As long as the corresponding prenatal screening and diagnosis can be carried out according to the norms, I believe that every father-to-be mother-to-be can have a healthy baby!
07
World Down Syndrome Day poster?