What is fetal malformation?
Fetal malformation refers to the structural or chromosomal abnormality of the fetus in the uterus. It is a birth defect and the main cause of perinatal death. Usually this is a relatively minor problem, such as an extra finger (toe) or a heart murmur. Rarely, children are born with serious deformities, such as heart malformation or spina bifida. Chromosome abnormalities, such as Down syndrome, are relatively rare.
Do pregnant women with fetal malformation feel anything?
Fetal malformation is generally known through examination, and there is no feeling as a expectant mother. If a woman's body temperature is too high in the early pregnancy, even if the child has no obvious appearance abnormality, the development of brain tissue may be adversely affected, showing mental retardation and poor learning and reaction ability.
Pregnant women can have all kinds of infectious diseases, all of which are elevated body temperature. Virus infection in early pregnancy can cause abortion, embryo stagnation or teratogenesis; Late acute inflammation can induce uterine contraction, leading to premature delivery and intrauterine hypoxia.
Can prenatal examination detect fetal malformation?
At present, hospitals mainly use B-ultrasound and Tang sieve to remove fetal abnormalities. B-ultrasound used to diagnose fetal malformation includes three-dimensional color ultrasound and four-dimensional color ultrasound. Three-dimensional color Doppler ultrasound can be done at about 24 weeks of pregnancy, and four-dimensional color Doppler ultrasound can be done at 20-28 weeks of pregnancy. Down's syndrome screening is mostly aimed at congenital stupid fetus caused by chromosome abnormality, and the best time is between 16 18 weeks of pregnancy.
The direction and scope of Tang sieve and four-dimensional deformability are different. The former mainly screens high-risk population of Down syndrome, while the latter mainly excludes fetal morphology. Both are necessary examinations during pregnancy.
Some treasure mothers will ask, can all fetal malformations be found through prenatal examination? The answer is no! There are eight kinds of fetal malformations that can't be detected by B-ultrasound.
1. Completely blind
Because the fetus is not stimulated by light in the uterus and will not open its eyes, it is impossible to diagnose congenital blindness or microphthalmia.
Step 2 stumble
There are many cases of water brain or water kidney, which will gradually appear in the third trimester of pregnancy.
Step 3 listen
The hearing of the fetus has developed at 5 6 months, but it is impossible to know whether the fetus has congenital hearing impairment.
4. Gastrointestinal obstruction
Gastrointestinal obstruction rarely occurs before 24 weeks of pregnancy, because the fetus rarely swallows amniotic fluid in the pre-pregnancy stage.
5. Abnormal limbs (fingers and toes)
Abnormal conditions, such as varus or eversion of hands and feet, polydactyly, syndactyly or lack of knuckles, are almost impossible to be diagnosed by ultrasound because the fetus is often in the state of clenching fists.
6. dwarfism
Some symptoms of dwarfism cannot be diagnosed at an early stage. Because when the fetus is 6 7 months old, it will gradually stop the development and growth of bones.
7. Congenital metabolic abnormality
Most abnormal biochemical and metabolic diseases, such as mucopolysaccharidosis, do not develop gradually until the baby is born and eats. Therefore, many fatal biochemical and metabolic abnormalities cannot be recognized before delivery, unless the mother gives birth to a baby with similar diseases.
8. Congenital heart disease
The atrial septum (the foramen ovale) and the arteriovenous catheter of the heart will gradually close after birth. Although heart disease is easy to diagnose at birth, it is impossible to know before birth.
How to avoid fetal malformation?
1, folic acid supplement
Medical research has proved that adequate folic acid supplementation before pregnancy can effectively prevent neural tube defects in embryos. Because folic acid is an indispensable substance in the development of nerve cells, folic acid in food is easily destroyed by China people's cooking habits, or eating too few fresh vegetables will hinder folic acid intake. Therefore, many years ago, the birth rate of neural tube defects in China was very high, and through folic acid supplementation before pregnancy, the incidence of neural tube defects has been greatly reduced in the past decade.
It is suggested that folic acid should be supplemented at least three months before pregnancy, and 400 micrograms of folic acid should be supplemented every day until three months before pregnancy, and the husband should take it together before pregnancy.
2. Regular physical examination and genetic counseling.
The causes of most birth defects are unknown, but couples with a family history of genetic diseases must have genetic counseling to analyze the probability of genetic diseases affecting the fetus.
3. Virus detection to prevent infection
During pregnancy, especially during the first three months of pregnancy, we should try our best to prevent infections, especially rubella virus, toxoplasmosis, herpes simplex virus, cytomegalovirus and Treponema pallidum. Immunization is the best prevention method.
T: Why can't prenatal examination sometimes find abnormal babies?
After pregnancy, every pregnant woman is undoubtedly working hard to get a healthy baby, so what can be done to better ensure a healthy baby? Why are deformed children born after prenatal examination?
These abnormal tests must be carried out during pregnancy.
NT exam: 1 1 week-13 weeks +6 days.
NT examination, also known as fetal neck zona pellucida scan, is to evaluate the possibility of Down's syndrome by detecting the thickest part of the silent zona pellucida below the fetal neck by B-ultrasound.
Basically, according to different places, the data evaluation is 3mm or 2.5mm, which means that if the test result is lower than this data, the risk is low; If it is higher than this value, but less than 6mm, it means there is a certain risk. It is best to make a diagnosis by further puncture or non-invasive. If it is more than 6mm, it means that the possibility of fetal abnormality is great, and it is best to diagnose it by puncture or villus biopsy.
However, according to individual differences and technical equipment limitations, the accuracy of nt detection is only 60%-70%, so even if NT detection is a bit unsatisfactory, pregnant women should not worry too much.
Tang sieve: 16- 18 weeks
The specific process of Tang screening test is to extract the venous blood of pregnant women, detect the concentrations of alpha-fetoprotein and chorionic gonadotropin in maternal serum, and then comprehensively calculate the risk value of Down syndrome in pregnant women by combining the gestational age, expected date of delivery, weight and pregnancy history.
After Tang's screening results come out, high risk or low risk will be directly displayed in the screening result column, and the numerical value will be displayed in the risk value column. In the case of 2 1- trisomy syndrome, the denominator value greater than 1000 is low risk, the value between 270- 1000 is critical value, and the value less than 270 is high risk, that is, the smaller the value, the higher the risk.
However, it is worth noting that screening is affected by other factors, which can only judge the possibility of Down syndrome in the fetus, but can't diagnose whether it is really Down syndrome, so no matter how high the risk is, the final result can't be explained.
Four-dimensional ovulation: 20-24 weeks
Four-dimensional exclusion method is the best way to observe the appearance, body surface, body structure, organ development, amniotic fluid and umbilical cord of infants. As far as its detection range is concerned, it includes head, face, spine, heart, heart cavity, abdominal organs, limbs and so on.
In other words, this kind of examination can only detect some problems that can be seen by ultrasound, but can't detect those problems that can't be seen, such as intelligence, metabolic diseases, hearing and vision.
Why can't the prenatal examination detect deformed children?
Many mothers have such doubts. Why did I have a prenatal examination and still get pregnant with a deformed child? This is not only a question of probability, but also related to the items of prenatal examination.
Intelligent problem
At present, only nt, Tang Sieve, non-invasive DNA and sheep puncture can detect Down's syndrome, while the first three methods are all screening methods, and their accuracy is NT Tang Sieve non-invasive DNA, so even if all three methods are done, it cannot be absolutely ruled out that there is something wrong with fetal intelligence. Although the noninvasive accuracy rate is as high as 99%, sheep puncture is a diagnostic method, which means that sheep puncture can only be confirmed.
Having said that, I don't mean to suggest that everyone make sheep clothes, but to choose according to their actual situation. For example, pregnant women over the age of 35 who are expected to give birth, have a family history, have an abnormal pregnancy history, nt, Tang screen or have no risk of creating a high risk, and have obvious abnormalities in B-ultrasound examination, it is best to directly make a sheep puncture diagnosis. Without these problems, most babies will be fine as long as they have ordinary prenatal examination items.
Four-dimensional restriction
Four-dimensional examination can detect most body surface deformities, head and face deformities and visceral deformities, ears, jaw arches, genitals and so on. Due to the technical limitations of the existing equipment, it is not within the detection range, and it is difficult to completely detect the number of fingers and toes due to occlusion and equipment reasons.
And what we care about most is hearing and vision. There is no way to detect during pregnancy, only postpartum screening.
Hide pregnant women
Sometimes there is no abnormality in the prenatal examination, which is also related to the practice of pregnant women, such as the most common glucose tolerance. In order to pass the examination smoothly, I have seen more than one pregnant woman start dieting a few days in advance, and then start eating and drinking again after the examination. Results The examination was purely for doctors, and some pregnant women even blamed the doctors for their poor business.
Other pregnant women will hide some family history, birth history of deformed children, abortion history, medication history and so on. As a result, doctors cannot accurately judge the state of the fetus and give the best advice.
Finally, in order for all pregnant women to have a healthy baby smoothly, we must fully cooperate with doctors, understand certain pregnancy knowledge, better prepare for pregnancy and cooperate with prenatal examination, minimize the birth of deformed children, and welcome the arrival of healthy babies.
Before answering this question, let's understand the following question. Even the most advanced and comprehensive prenatal screening and prenatal examination can not completely rule out the birth of deformed children. You can only say that you can avoid the birth of some deformed children and reduce the birth of deformed children. That's why obstetricians won't tell you that your baby is normal, only that there is no abnormality at present.
At present, the conventional prenatal screening methods are nothing more than Down's screening, nt examination, non-invasive DNA examination and large-scale abnormal examination. These are all screening for endemic diseases, that is to say, screening for diseases with high incidence, so many rare diseases are not within the screening scope, and some minor deformities cannot be screened out.
The above expression is an objective problem, but as a treasure mother, it is best to choose a more reliable hospital checkup. After all, some examination items are related to the doctor's experience. Some doctors can do it, and some doctors just can't. For example, in a hospital, Xiaoli's system ultrasound was normal, but later it was found that the baby had no stomach bubbles. This is a question of technology and responsibility. After all, the system B-ultrasound depends on the gastric bubbles.
To sum up, the birth check-up only reduces or avoids the birth of a certain kind of defective children, but it cannot avoid the birth of defective children. Nearly 6% of children with defects are born in China every year, including structural and functional defects. Good luck with your pregnancy.
Hello, I'm happy dad's diary, and I'm glad to answer your question.
0 1
There was a hot search on the news last year:
A mother had a prenatal check-up on time during pregnancy, and the results of each prenatal check-up were healthy. As a result, when the baby was born, it was found that the baby had only one arm, which means that the baby was deformed at birth.
To tell the truth, such a thing is hard for anyone to accept, and at the same time, the question of "why can't the prenatal examination detect the baby's deformity" is suddenly placed in front of many mothers.
So, why do prenatal examinations sometimes fail to detect abnormalities?
02
In fact, prenatal examination is the most effective way to reduce birth defects at present. Ultrasonic examination can find a considerable number of infants' malformations or developmental abnormalities in advance, which is also the greatest significance of prenatal examination. For example, four-dimensional color Doppler ultrasound can clearly see the baby's condition, and if there are common malformations, it can be found in advance.
However, not all malformations can be detected.
Some abnormal prenatal examinations can't be detected at all.
For example, congenital malformations caused by chromosomal abnormalities, or some tiny malformations in relatively small parts, cannot be detected by the current medical level. After all, the resolution of ultrasound is very limited, and there are still some technical imperfections, so this kind of deformity is likely to be missed.
Due to the limitation of inspection, some anomalies are difficult to find.
In the process of prenatal examination, ultrasound examination also has great limitations.
For example, the situation of mothers' abdomen, the baby's posture, and whether there is umbilical cord occlusion. These factors will affect the final exam results. For example, the baby's posture is not conducive to observation, there will be many body parts that are difficult to find, and it is easy to be missed or misdiagnosed.
Some abnormalities are gradually revealed as the baby grows up.
There are also some abnormalities or deformities that gradually become obvious as the baby grows up and can be detected. Moreover, in medicine, there is no clear boundary between normal and abnormal, which means that deformity is difficult to be detected if it does not develop to a certain stage.
For example, the length of the femur in the baby's last checkup was not very good, but it was within the standard range. However, the following examination showed that the femur length was insufficient, that is, the baby's bone development was abnormal. It is difficult to accurately judge this type of abnormality only by one or two physical examinations.
03
In fact, the present prenatal examination can find the baby's deformity to a great extent, but the baby's growth and development is a dynamic process, and the current medical level has not reached the point where 100% is determined. Mothers should treat the results of prenatal examination more rationally.
Thank you for your invitation. I'm Shen Huan, a reproductive doctor. I'm glad to answer this question for you.
Ultrasound examination is only screening, and the abnormality is diagnosed through the influence of ultrasound. However, not all malformations can be definitely diagnosed by ultrasound, and the diagnostic rate is affected by equipment and technology.
Prenatal examination is an item that every pregnant mother should do. Time is long and there are many kinds. Even after prenatal examination, many deformed children are still born.
Then why don't you have a prenatal examination, and you can't detect deformed children?
This is not only a question of probability, but also related to the items of prenatal examination. So, let's look at some common problems.
down syndrome
At present, only nt, Tang Sieve, non-invasive DNA and sheep puncture can detect Down's syndrome, and the first three are screening methods, and their accuracy is NT Tang Sieve non-invasive DNA, so even if all three are done, it cannot be absolutely ruled out that there is something wrong with fetal intelligence. Although the noninvasive accuracy rate is as high as 99%, amniocentesis is a diagnostic method, which means that sheep puncture can only be confirmed.
However, it is not recommended that you do sheep piercing. Only pregnant women who are over 35 years old, have a family genetic history, have a history of abnormal pregnancy, and have no high risk or obvious abnormality in nt, Tang screening or B-ultrasound examination, it is best to make a direct diagnosis by sheep puncture. If pregnant women do not have the above problems, most babies will have no problems as long as they have ordinary prenatal examination items.
Four-dimensional large exclusion test
Four-dimensional examination can find out most body surface deformities, head and face deformities, visceral deformities and limb deformities. However, due to the technical limitations of the current equipment, the fine structures of some organs such as ears, jaw arches and genitals are not within the scope of detection, and the number of fingers and toes is difficult to be completely detected due to occlusion and equipment, so it does not mean that the baby will be fine if it is deformed.
And what we care about most is hearing and vision. There is no way to detect during pregnancy, only postpartum screening.
Therefore, in order for all pregnant women to have a healthy baby smoothly, we must fully cooperate with doctors, understand certain pregnancy knowledge, better prepare for pregnancy, and cooperate with prenatal examination to minimize the birth of deformed children, but we also need to know that even if the prenatal examination has passed, there is still a small chance of giving birth to deformed children.
Giving birth to a healthy baby is the wish of all parents, but there is still a very small probability of giving birth to a deformed baby. Many people will be surprised, why do you still give birth to deformed children on time? The main reasons for this problem are reflected in the following two aspects.
At present, the prenatal examination program can't rule out all fetal malformations.
Prenatal examination is to diagnose the health status of the fetus through corresponding medical technology, but now many prenatal examination items can only carry out structural examination, such as judging whether the fetus is abnormal or not. However, many malformations show functional problems, such as cerebral palsy, which is a functional disorder of the brain. The current prenatal examination technology can not check this functional problem.
It can be seen that although prenatal examination is an effective means of fetal abnormalities, the existing medical technology is still limited, and many abnormalities still cannot be found through prenatal examination. At present, the main malformations that cannot be detected are fetal hearing, vision, dwarfism, mental retardation, congenital metabolic defects, gastrointestinal obstruction and so on.
One of my classmates in Dabao was born short-sighted, and it was not until he was over 3 years old that he discovered that the existing medical technology like this would definitely fail the prenatal examination.
The existing inspection items cannot guarantee the accuracy of 100%.
In order to ensure prenatal care, pregnant women need to face multiple prenatal examinations during pregnancy, and the time and items of each prenatal examination are clearly defined. However, due to the limitation of medical technology, many inspection items cannot guarantee the accuracy of 100%. For example, screening for Down syndrome generally requires NT examination and screening for Down's blood during pregnancy. If there is a high risk, non-invasive DNA and amniocentesis are needed. After a complicated screening process, the incidence of Down syndrome is still as high as 1/800- 1/600.
In addition, even if the troubleshooting success rate of some prenatal items is high in theory, it will still be affected by the operation of medical equipment and the technical level of prenatal doctors in the specific process of prenatal examination. For example, medical equipment is not maintained in good operation and maintenance, or medical equipment is under high load, which may affect the results of prenatal examination, leading to false detection and missed detection, so that abnormal fetuses can not be effectively detected.
In a word, prenatal examination is not a panacea, and it can't screen out deformed children 1 0,000%, but it still has a high success rate. Therefore, in order to ensure the birth of a healthy baby, prenatal examination should be done on time. Of course, pregnant women must also strengthen their health care during pregnancy.