This kind of fetal chromosomal problem is more susceptible to young pregnant women! Listening to persuasion is more effective in preventing it

Today is World Sleep Day, March 21, which is also World Down Syndrome Day, and today I want to talk about Down syndrome.

In our traditional understanding, the advanced age of the mother is an important reason for the pregnancy of a child with Down syndrome, and in fact, the clinical screening of pregnant women over the age of 35 is also more stringent.

However, real-world analyses have found that maternal age is not an immunity to Down screening, as a growing body of research has found that

01 Up to 85.8% of the mothers of children with Down syndrome were under the age of 30

A study of infants with trisomy 21 who had been treated in the pediatric department of our hospital in the past three years found that there was one child born to a 35-year-old mother and one child to a 40-year-old mother.

Other factors were mainly the first pregnancy, the first child accounted for 71.4%, and the ratio of urban and rural children was 1:1, and there was no obvious difference between urban and rural areas.

Rural mothers had a history of pesticide exposure before giving birth, while 6 mothers in urban areas had no clear history of exposure to toxic substances.

Another study in Zhuhai found that 96 cases of trisomy 21, 21 cases of prenatal diagnosis, and 75 cases of postnatal diagnosis were detected through prenatal diagnosis and postnatal diagnosis within three years.

When investigating the maternal age of these trisomy 21 fetuses, it was found that

In recent years, foreign research on multi-thinking has also suggested that

This suggests that the age of occurrence of trisomy 21 tends to be younger, suggesting that there are other factors affecting the nondisjunction of chromosome 21.

02 Non-age factors that lead to trisomy 21

Trisomy 21 is caused by the failure of chromosome 21 to segregate during meiosis of sperm and egg cells.

It has long been widely believed that the main risk factor for non-disjunction of chromosome 21 is the increased age of the mother.

Data show that 80% of the extra chromosome 21 comes from the mother, and children with trisomy 21 can be born at any age of the mother, but gradually increase from the age of 30.

As women age, the protective mechanisms that ensure accurate chromosome separation, such as spindle polymerization, are weakened by the "wear" on the back of the checkpoint, which eventually leads to chromosomal abnormalities during meiosis.

Among them, the frequency of mothers aged 25-29 is 1:1350, and the frequency of mothers over 45 years old is 1:50.

However, the above study found that the mother's youth is more likely to lead to the live birth of Down's children, which subverts the previous cognition, and a comprehensive literature analysis believes that it is manifested in the following aspects.

According to the investigators' analysis, this may be mainly due to the possible genetic predisposition of young pregnant women giving birth to children with trisomy 21.

Polymorphisms in folate metabolism-related genes such as maternal methylenetetrahydrofolate reductase and methionine synthesis reductase may cause abnormal folate metabolism, which is closely related to the occurrence of trisomy 21.

Mutations in folate metabolism-related genes have an effect on methylation patterns in chromosome 21 sufficiency and segregation of key regions.

Researchers believe that there are many factors that contribute to the younger mother's childbearing age, because the development of women in the fetus has reached the prephase of meiosis I, and it should be maintained in this period in the future.

An ovary has the potential to form about 400,000 eggs, but only about 400 eggs reach maturity.

Modern industrial pollution and newly synthesized chemicals are constantly used in various fields, such as pesticides, preservatives, drugs, food additives, cosmetics, automobile exhaust, etc.

Many young pregnant mothers think that trisomy 21 mainly occurs in elderly pregnant women, and they are relatively young, so they ignore the importance of relevant examinations.

A foreign study found that long-term exposure to organic solvents in the production worker group was an important predictor of MI non-separation.

Therefore, the prevention of trisomy 21 must be taken seriously by every pregnant woman, and even families without any high-risk factors are not something that can be taken lightly at a young age.

Our body secretes a hormone during sleep, which is melatonin.

Therefore, it is no accident that World Sleep Day and World Down Syndrome Day are on the same day, and it is also important to reduce trisomy 21 and sleep well in young women.

03Strictly adhere to the four lines of defense for screening

Ultrasound screening is the most important means in the screening of trisomy 21, and a retrospective study found that

Some studies have found that in the fetal ultrasound manifestations of trisomy 21, trisomy 18, and trisomy 13,

Therefore, NT ultrasound in the first trimester is like the first "demining exercise", which is combined with serological screening to form a double insurance.

The mid-term Down screening is the second calibration of the Down screening test.

For the case of the risk value on the street, the new non-invasive DNA test can capture the fetal chromosomal signal through the maternal blood with an accuracy of more than 95%.

Amniocentesis remains the gold standard of diagnosis when the test is abnormal, although there is a 3 in 1,000 risk of miscarriage (but this risk is not a technical factor).

04 Tang sieve high-risk, non-invasive, low-risk, still do sheep wear?

Sister Quan once heard such a story, a girl Tang was screened for a high risk of trisomy 21, and the local doctor recommended amniocentesis, but she was more worried about the risk of miscarriage, so she chose non-invasive DNA.

The non-invasive results came out quickly, suggesting that T21, T18, and T13 were all low risk, and if this was not a careful girl, it is estimated that the examination would come to an end here.

The girl was still not at ease, and did a sheep wear again, but the sheep wore a high risk of 21 trisomy, which made the girl very puzzled, what is going on?

Here we need to know that non-invasive DNA testing is the genetic material related to the fetus.

Yes, you read that right,

The fetus and placenta come from the same fertilized egg, and in most cases their genetic material is exactly the same, and the placenta can act as a spokesperson for the baby, and testing it can tell the condition of the fetus.

But

This is too instructive for the sisters in our circle,

The children of our sisters and sisters are precious children, so prenatal diagnosis is more meaningful to us, and the hospital generally requires the delivery age of 35 years old to be the target group for sheep wearing, but Sister Circle believes that precious children are worthy of sheep wearing.

Regardless of age, every mother shoulders the sacred mission of giving birth to a new life, and there is no immunity from Tang Sieve when young, and scientific prenatal examination is the first precious gift we give to the baby.

Solemnly declared

The content published on this account is only for information sharing, this account does not do any form of marketing promotion, and the views of the article cannot be directly used as medical diagnosis or health intervention suggestions. Talk to your healthcare provider before taking any preventive or curative measures.

No gossip and rumors

Don't be an official account that exists only for the number of forwards

Always care about real data and documentary arguments

On the way to hold the baby, I am willing to accompany you through the most helpless years

——THE END——

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