Hello, very happy to answer your questions, Down's syndrome is just a screening test in the maternity test, the accuracy rate is only 60-70%, so it can not be used as a final diagnosis, even if the Down's syndrome is found to be a high risk, there are still chances of reversal.
There are many reasons for the high risk of Down syndrome, such as viral infections, radiation, blind medication and so on are the reasons for the high risk of glucose screening, if the Down syndrome suggests that the high risk of amniocentesis can be carried out again to do the final diagnosis, if you are worried about the risks of the puncture, you can also choose to non-invasive genetic testing, but it is only a screening can not be seated in the diagnosis.
The Down syndrome is a test of the hormones in the blood of the mother, coupled with the gestational weeks and weight, and finally calculated using the formula, so I want to tell you that the results of the test is very susceptible to a variety of factors, so the accuracy is not high.
I hope my answer can help you!
Down's screening high-risk, especially the word high-risk people scared, often see pregnant women with a high-risk list to ask me, now on the Down's screening of the most confusing aspects of the content to explain to you.
One. The first thing you need to do is to get your hands on a new pair of shoes or boots. Down's syndrome screening is a test to check for trisomy 13, trisomy 18, trisomy 21, generally choose between 11 and 14 weeks can be done (recommended in Europe and the United States), can also be done between 16 and 20 weeks (Chinese routine). The Down's syndrome screening test we do in China is a blood test at around 16 weeks, checking for alpha-fetoprotein, free chorionic gonadotropin, and free estriol, and calculating the ratios through the software, the machine in domestic hospitals now usually sets the value at 1:270, and exceeding this value is considered high-risk. If one of the three indicators exceeds the standard, most of them will become high-risk. Even if all the obstetric tests before the Down's syndrome are normal, the three tests may be abnormal, and high-risk.
II. What to do if you are high risk for Down's syndrome? According to the national guidelines, it is recommended to do prenatal diagnosis, specific measures:
1. Chorionic villus aspiration: 11 to 14 weeks, if the discovery is made before 16 weeks can be done, 16 weeks before the Down's syndrome should not be done.
2. amniocentesis: advocate in 16 to 20 weeks to do , if the Down's screening appears to be a high risk, can be done at this time is best, amniocentesis has a certain risk of miscarriage, the probability of miscarriage is about one percent.
3. Umbilical cord blood sampling: generally can be done after 24 weeks, now more than 32 weeks many hospitals no longer do.
3. The first thing you need to know is whether or not you can have a high-risk fetus with Down's syndrome, and whether or not you're going to have a deformed baby. I can say that Down's screening high risk, it is recommended to do prenatal diagnosis, if there is no chromosomal abnormality, completely can be, chromosomal abnormality, the probability of fetal malformation can be reduced to one in ten thousand. The fact is, the most important thing is that you have to be able to get the best out of your life, and you have to be able to get the best out of your life, and you have to be able to get the best out of your life.
Summary: Down's high risk is detected through the blood test indicators, one of the abnormalities will be high risk, need to do prenatal diagnosis to determine whether there is a fetal chromosomal abnormality.
Although the accuracy of the Down's syndrome test as a whole still needs to be improved, the accuracy of the early Down's syndrome test is still possible, not always high risk.
How does the early Down screening risk come about?First of all, it is definitely based on the values of beta-hcg and pregnancy-related plasma protein A. Secondly, it should be combined with maternal age, weight, and gestational week. Maternal age is a very important factor here, and carries a lot of weight. If there is indeed a problem with the current embryo, a high risk of Down's syndrome is natural, and secondly, generally speaking, the age is high, and the likelihood of a high risk of early Down's syndrome is very high.
Is early Down screening worth it?
This is how I look at the question, if it is a pregnant mother is relatively young, and there is no relevant family history, no previous history of adverse induction of labor, and there are no other high-risk factors, it is also possible to prefer early Down screening. I have to admit, the price advantage of early Down screening is obvious.
Considering only accuracy, what is the best choice?
Early Down screening is certainly not always high risk, if it is always high risk to find the problem, even if you find a solution. Risk values for Down's syndrome
The rationale for Down's syndrome screening is based on the fact that abnormal fetuses secrete hormones that are abnormal to those of normal fetuses, and then combined with the age of the pregnant woman, the gestational week of the fetus to comprehensively assess the risk of selecting those 5 people who are furthest away from the normal level out of 100 people as high-risk. These 5 individuals were considered to be at high risk for chromosomal abnormalities.
So in Down's screening, on average, 5 out of every 100 people are destined to be high risk because that's how our experimental thresholds are taken. So the percentage of high risk is 5%, and most are low risk. So it's not mostly high risk, and that would defeat the purpose of the test.
As another example, we randomly identify 100 men of the same age group, and consider the 5 shortest of those 100 to be "abnormal", and we consider those 5 to have stunted growth defects. However, in reality, 2 of these 5 people may be normal short, there is no developmental defects, so it is a "misdiagnosis". Of the 95 people who are considered normal, perhaps 3 have developmental defects, which is a missed diagnosis. In fact, most tests use a similar approach to determine diagnostic thresholds, so there is always a risk of underdiagnosis and misdiagnosis.
So a high risk for Down's screening is only indicative of a high risk of disease (about 10% problematic, 90% normal misdiagnosis), and a low risk for Down's screening is only indicative of a low risk of disease, not no risk (about 20%-30% missed diagnosis).
Winter's pregnancy for Down's syndrome screening, the test results are high risk, in order to confirm whether the baby in the belly is really a child with Down's syndrome, the doctor recommended that Winter do amniocentesis to confirm the diagnosis.
Dong'er was also pregnant for the first time, she and her husband encountered such a situation, suddenly panicked.
Dong'er hurriedly called the leader to ask for leave, but also with a crying voice, the leader listened to her description, began to comfort her: "Don't panic, I was Tang screening is also high risk, but you see my son is not healthy? The first thing you need to do is to get your hands on a new pair of shoes or boots, and then you'll be able to get your hands on a new pair of shoes or boots.
Dong'er listened to the leader's consolation, began to slowly calm down, the mind also returned to the rationale.
Through all aspects of understanding and learning, and consulting the doctor, Dong'er immediately went to do a non-invasive DNA test, the final results of the low-risk, and also comes with an insurance policy, if the birth of a Down's child, the insurance company will compensate for a certain amount of money, the couple was relieved.
Until they gave birth to a healthy daughter, Winter and her husband were completely relieved.
Getting it right:
Why are Down's syndrome results always high risk?
Elevated levels of certain specific substances present in the mother's blood serum from the fetus and the placenta indicate that the fetus is at risk for Down syndrome. These substances include alpha-fetoprotein (AFP), human chorionic gonadotropin (HCG), estriol (uE3), PAPP-A, and inhibin A.
Down's syndrome screening is performed by taking a sample of a pregnant woman's blood serum, and extracting the results of the tests for alpha-fetoprotein, human chorionic gonadotropin, human chorionic gonadotropin, and human chorionic gonadotropin. Gonadotropin, free estriol concentrations are extracted and then combined with the mother's gestational week, weight, and age to calculate the probability of the fetus having Down syndrome.
①Week of gestation
Week of gestation calculations are often less accurate and can affect the results of Down's syndrome screening.
Many expectant mothers don't know the exact date of conception, and this is calculated based on the first day of your last normal menstrual period, which requires a regular menstrual cycle and assumes that you will ovulate 14 days after the first day of your period.
There are also some pregnant moms who are unsure of the date of their last normal period or have irregular menstrual cycles, which can be presumed based on the first ultrasound, but it's not absolutely accurate.
②Weight
A pregnant mother's excessive weight can affect the results of Down's syndrome screening.
Some people don't have a low weight no matter how much they control it, and some gain too much weight during pregnancy.
Modern society, the conditions are better, there are many pregnant mothers in order to give birth to a healthy and smart baby, for their own body, only think of increasing nutrition, ignoring the matter of weight control, resulting in excessive weight gain, which will also affect the results of the test.
③ Age
In modern society, there are many women who are older when they get pregnant, and the older they are, the higher the calculated risk.
Hospitals already don't recommend Down's syndrome screening for older women over 35.
Due to various pressures, or to enjoy the single life, or to enjoy the two-person world, or to wait until the conditions are better and want to have a second child, there are many women who are not young when they get pregnant, and some of them have already crossed the line into the ranks of the senior maternal age.
More than 30, more than 40 years of pregnant mothers are also very common, some time ago, there is a 67-year-old pregnant woman who gave birth to three children.
④: Multiple births
Pregnant mothers with multiple pregnancies have higher serum levels of these substances, so the test results are unreliable.
Let's see what the netizens say:
Netizen 1: We do not do the Down syndrome now, the hospital on the local household registration of pregnant women free of charge to do non-invasive.
Netizen 2: When I was pregnant with my first child, I didn't even do the Down's syndrome, but when I was pregnant with my second child, the Down's syndrome was a critical risk, so I discussed with my family and said that I should do the non-invasive, and spend the money to buy peace of mind, and that I'd be satisfied if my children were healthy and well, and that there is nothing more important than my health.
Netizen 3: I was 36 years old when I gave birth to my second child, and the doctor said directly that the Down's syndrome could not be passed, and that the amniocentesis was the safest, and that you could not afford to gamble on it. I'm not sure if you're going to be able to get a good deal on a new one, but I'm sure you'll be able to get a good deal on a new one. Now the second baby is 2 and a half years old, lively and lovely, pregnancy check on the doctor's advice must be listened to, because the consequences can not afford.
Netizen 4 : I wanted to do non-invasive when I was pregnant, but because of the pre-pregnancy acceptance of blood donation, so non-invasive will not be accurate, but the doctor is not in favor of amniotic fluid penetration, because of the low platelets, to go back to their own considerations, at that time, good torn ah.
Star House Parenting: If the conditions of the pregnant mother are suitable, you can consider doing non-invasive DNA or amniocentesis, the accuracy is more guaranteed.
Now the maternity check is very right, pregnancy Down screening early high-risk, personal advice to pay more attention to some.
Although do not have to completely believe, there are many people say it is only a temporary indicator. But my words will be very careful, careful makes all the boat.
Pregnancy pregnancy was a great responsibility, in line with the attitude of responsibility for the baby, the doctor let do the examination a not pull.
Early pregnancy Down syndrome that is high risk to listen to the doctor's advice, let do what check to do. The first thing you need to do is to get your hands on a new one, and then you'll be able to get a new one.
After all, in order to baby are worth.
Many pregnant women know that they need to have a Down syndrome test in mid-pregnancy, but few of them know that Down syndrome is also divided into early Down syndrome and middle Down syndrome. According to what you said, the early Down syndrome test should refer to the early Down syndrome.
Early Down syndrome is usually checked at 12 weeks, and when I was pregnant before, the early Down syndrome was done together with NT, and the result was low-risk, but according to my understanding, many people with the same title, the early Down syndrome is mostly high-risk, but the later results of the middle Down syndrome, including the results of non-invasive, is low-risk, which is the reason why it is?
1. Factors affecting the results of the Down syndrome.
First of all, if it is over 35 years old pregnant women and pregnant mothers with more than one child, the results of the Tang screening is very likely to be high-risk, which is affected by the factors of age and the number of fetuses.
Secondly, if the mother has had a poor diet or has not had enough rest for a long period of time before the screening, it may also affect the results of the test, which is affected by the mother's own physical condition.
Finally, because the results of the Down screening is not 100% accurate, sometimes by the interference of medical equipment and some deviation, so there is a high-risk situation, which is affected by the medical device factors.
2.
The first point is that pregnant women should control their diet reasonably before doing the Down syndrome, focusing on lightness, avoiding too much spicy and fried things, eating more fruits and vegetables, and adjusting the state of the body.
The second point is that pregnant mothers need to ensure adequate sleep and avoid too much exertion.
The third point is that if the result of the Down screening test shows high risk, the pregnant mom doesn't need to worry too much, most of them are fine after doing non-invasive DNA.
To summarize, it is really easy for pregnant mothers to worry during pregnancy because of unsatisfactory test results, in fact, these so-called maternity programs are probabilistic, which means that there may be errors, so pregnant mothers do not have to worry too much, and if there is a problem, further testing is done.
Before the Down's syndrome screening test, pregnant mothers in 12 weeks, now NT, is the fetus NT index will not exceed 3.0, if more than then, you need to review, and to 16 weeks, pregnant mothers began to do Down's syndrome screening, this project is also a means of checking the Down's syndrome, but Down's syndrome screening is often High-risk, a lot of pregnant mothers every time they see the word, legs are soft, and the Down's syndrome, the Down's syndrome, the Down's syndrome, the Down's syndrome, the Down's syndrome, the Down's syndrome, the Down's syndrome, the Down's syndrome, the Down's syndrome, the Down's syndrome, the Down's syndrome. After all, their hard work pregnant, if the baby has any deformity, the fetus is not good, deformity is very difficult to cure, many pregnant mothers do not know Down's screening accuracy is only 60% -70%, so if the test results are high-risk, then pregnant mothers should not be too anxious.
How is the Down's syndrome test
Down's syndrome test results: the doctor will be the mother's blood concentration of alpha-fetoprotein, human chorionic gonadotropin, combined with the weight of the pregnant woman, gestational weeks, the expected date of birth and other indicators, and then through the calculation of the equipment, to arrive at the risk coefficient of the fetus with Down's syndrome.
But a lot of pregnant mothers weight fluctuation is not normal, the gestational week is not accurate, the gestational week is not allowed to be heart is also menstrual disorders, ovulation irregularity, then naturally affect the results of the Down's syndrome screening. So pregnant mothers see a high risk, do not be too anxious, may be just because they have gained weight, or the gestational week is not correct.
When a pregnant mom's Down's test results are high risk pregnant mom what to do
The first step is to review the test again, if the test report is still high risk, then you need to do non-invasive DNA or amniocentesis.
Pregnant mothers can choose non-invasive DNA, non-invasive DNA testing is not dangerous, just draw blood, blood blood from the pregnant mother, and then extracted from the blood of the fetus free DNA fragments for sequencing, the process is very simple, and the accuracy rate is 99%.
Amniocentesis, there is a certain danger, there is a one percent miscarriage rate, the doctor will pass the ultrasound, and then look for a good needle, look for a good puncture position, the doctor in the pregnant mother's stomach coated with alcohol, with a long needle into the pregnant mother's stomach, long needle through the abdominal wall of the pregnant mother to the uterine wall, to help the pregnant mother's uterus to extract the right amount of amniotic fluid, the pregnant woman to bed rest for 2 hours.
Amniocentesis is a diagnostic technique that is considered the gold standard for chromosome testing.Amniocentesis is the use of a long thin needle to puncture the pregnant mother's stomach, and then to the pregnant mother's uterus to extract amniotic fluid, may cause amniotic fluid outflow and bleeding, and there is a possibility of injury to the baby, especially after the 24th week, the risk of doing amniocentesis is greatly increased
As long as the amniocentesis is done and the results of the test are chromosomal abnormalities, there are chromosomal deletions and duplications, may be with the evolution of the fetus, there will be improve, but pregnant mothers still need to consider whether to keep the child, to make a timely decision, so that the fetus is large is not good to induce labor, and it is harmful to the pregnant mother.
The Down syndrome screening test, which is a computerized calculation of risk, is a test of the peripheral blood of a pregnant woman to check the concentration of alpha-fetoprotein, HCGb, and free estriol, and then combines this with the weight, gestational age, and age of the mother of the child.
However, today's young people are living under great pressure to get married, buy a house, buy a car, and have a baby, and also face the problem of work, so the age of women's marriage and childbearing age is getting older and older, coupled with the fact that many women of advanced maternal age to join the ranks of wanting to have a second child. So the percentage of high-risk Down screening has been raised in this way.
The main tests for Down screening are trisomy 21, trisomy 18, and trisomy 13, of which trisomy 21 is more accurate and the other two are less accurate. There are two types of screening tests: Early Tang and Mid Tang, Early Tang at 11-13 weeks +6 weeks, and Mid Tang at 16-20 weeks.
There are three types of Down screening results: low risk, critical risk, and high risk. Low risk, which indicates a low probability of developing Down syndrome; critical risk is generally recommended for pregnant women to do non-invasive DNA, and high risk is generally recommended for pregnant women to do puncture.
Early Down, if high-risk, can do chorionic villus aspiration at 11 to 13+6; Middle Down, if high-risk, can do amniocentesis at 16 to 20 weeks; and if fetal chromosomal abnormalities are suspected in late ultrasound screening, cord blood aspiration can also be done at 24 to 32 weeks.
The above picture shows that there is a risk of infection or miscarriage of about 3 per 100,000 people. Usually, puncture is only recommended if there is a high risk of Down's syndrome or a high risk of non-invasive testing, or if there is a risk of fetal abnormality on later ultrasound.
Overall, Down's syndrome is a screening test, not a prenatal diagnosis. The overall accuracy of screening is not very high (only about 60-70%) and the positive predictive rate is even lower (about 3%). So, in the future, Down screening will most likely be replaced by non-invasive DNA.
In short, pregnant women who have a high risk of Down syndrome don't have to worry too much. Because the Down's syndrome positive prediction rate is only 3%, that is to say: among 100 test results in the same period, only 3 of the final diagnosis by amniocentesis is really Down's syndrome.
The role of Down's screening in pregnancy is to detect fetal abnormalities as early as possible so that an amniocentesis appointment (18-22 weeks) can be made earlier. If some of the middle Downs are done when they are almost 20 weeks, this often does not allow for an amniocentesis appointment. Even some need to have a higher risk cord blood puncture.
The topic turns back to why early Down's screening in pregnancy is always high risk, this is essentially related to this technology, I will not go into the details. Whether it is the middle Tang or early Tang have the disadvantage of high positive rate and low detection rate, so it is extended the need for early Tang + middle Tang combined screening, early Tang + middle Tang + NT combined screening, these are to improve the detection rate.
In fact, I personally recommend that you try to do a non-invasive, non-invasive DNA test is generally 12-22 weeks, only 21, 18, 13 chromosomes, but most of the chromosomal abnormalities are the three, especially the 21-trimester, which accounted for more than half of the chromosomal abnormalities.
To summarize, Down's syndrome screening during pregnancy has a high positive rate and a low detection rate, and it is recommended that non-invasive DNA testing be done directly when the situation permits. Good luck with your pregnancy.