Why do you need NT examination during pregnancy? The purpose of nuchal translucency examination is to diagnose chromosomal diseases in early pregnancy and find fetal abnormalities caused by various reasons.
Because the study found that in 1 1- 14 weeks of pregnancy, if the fetus is down's syndrome or cardiac dysplasia, the transparent layer of the neck will thicken. The thickening of nuchal translucency is related to structural abnormalities such as fetal karyotype and fetal congenital heart disease. The thicker the transparent layer of the neck, the greater the probability of fetal abnormality.
Is there a risk of malformation in fetuses with high NT value? NT examination is best done at 1 1- 14 weeks of pregnancy. After 14 weeks, it will be inaccurate, and the time of Bitang's syndrome is earlier. NT examination is mainly determined by B-ultrasound, and the final measured value is less than 3 mm. If it exceeds 3 mm, further examination, such as amniocentesis, should be considered. ..
According to relevant statistics, the detection rate of Down syndrome can reach more than 85% through nt examination and blood test.
If the pregnant mother is found to be a high-risk group through cervical zona pellucida examination, it does not mean that there must be something wrong with the fetus. Further diagnostic tests (including chorionic villi collection at 1 1~ 15 weeks or amniocentesis at 16 ~ 20 weeks) are needed to determine whether the fetus has Down syndrome or other congenital diseases.
In normal pregnancy, at 1 1- 14 weeks, the thickness of nuchal translucency increased slightly with the gestational age, and it was normal when the measured value was less than 2.5mm, and thickened when it was greater than or equal to this value. Clinically, most of the fetuses with thickened transparent layer of the neck were detected at11-kloc-0/4 weeks of pregnancy, and no abnormalities were found after birth, but a considerable number of fetuses were diagnosed with chromosomal abnormalities, anatomical structural abnormalities or some genetic syndromes. If there are no other obvious abnormal ultrasonic manifestations during the pregnancy of 1 1- 14 weeks, ultrasound must be rechecked several weeks later, because most fetal malformations can only be screened and diagnosed by ultrasound after 17-20 weeks.
Who recommends NT exam? In addition to pregnant women who have decided to have amniocentesis, it is best for pregnant mothers to have Down's syndrome maternal blood screening and fetal neck zona pellucida examination to ensure the birth of healthy babies.
In addition, for pregnant women with difficulties, pregnancy complicated with uterine fibroids, IVF and other elderly women. Because amniocentesis may increase the risk of miscarriage, and pregnant women have difficulty getting pregnant in the future, or it is difficult to get pregnant again, amniocentesis may not be done. By examining the zona pellucida of fetal neck and screening Down's syndrome in maternal blood, a very high level of prediction can be achieved.
Wonderful recommendation:
Optimal time of four-dimensional color Doppler ultrasound
B-ultrasound data to see the sex of fetus
Fetal heart monitoring
Fetal sex prediction
Boys and girls should know.