The nuchal translucency scan also called the NT scan uses ultrasound to assess your developing baby's risk of having Down syndrome DS and some other chromosomal abnormalities, as well as major congenital heart problems. The NT scan measures the clear translucent space in the tissue at the back of your baby's neck. Babies with abnormalities tend to accumulate more fluid at the back of their neck during the first trimester, causing this clear space to be larger than average. The NT scan is not invasive. The NT scan must be done when you're between 11 and 14 weeks pregnant, because this is when the base of your baby's neck is still transparent. The last day you can have it is the day you turn 13 weeks and 6 days pregnant.
The primary reason for this scan is to conduct a nuchal translucency test. The term nuchal translucency refers to a pocket of fluid which is present at the back of the baby's neck.
A higher volume of fluid can be an indication that the baby may have Down's syndrome.
This is not a definitive diagnosis however. It can only estimate the risk of the baby having the condition. There are two diagnostic tests available which will give a clear diagnosis; these are known as chorionic villus sampling CVS and amniocentesis - both of these carry risks of miscarriage.
The secondary objective of this scan is to ascertain the due date of the baby. This is done by measuring the baby's body.
Generally, your sonographer will be able to conduct the dating and nuchal translucency measurements at the same appointment, but if it is too early to get a clear image for the nuchal translucency then you will be asked to return at a later date.
Your scan will also confirm that the baby's heart is beating normally.
For some parents to be, the scan can bring some exciting surprises as it will show how many babies are present! You will be told during your appointment what your estimated due date is. This is based on the measurements of the baby.
Occasionally this date is adjusted after your next scan, particularly if this scan has happened quite early. You will have to wait a few weeks for the results of the nuchal translucency tests because the risk factor is calculated using both the scan and the results of a blood test which will be conducted separately.
You will receive a letter after the results of your blood tests have been processed and the letter will tell you what the estimated chances are of your baby having Down's syndrome. An NT scan is a common screening test that occurs during the first trimester of pregnancy. But too much clear space can indicate Down syndrome, or might show another chromosome abnormality like Patau syndrome or Edwards syndrome.
Our body cells have many parts, including a nucleus. The nucleus holds our genetic material. In most cases, the nucleus has 23 pairs of chromosomes, which are equally inherited from both parents. Individuals born with Down syndrome have an extra copy of chromosome This condition affects 1 in every babies born in the United States.
Patau syndrome and Edwards syndrome are rare and often fatal chromosome abnormalities. Unfortunately, most babies born with these abnormalities die within the first year of life. This test can also include blood work to measure your levels of plasma protein and human chorionic gonadotropin HCGa maternal hormone.
Abnormal levels of either may indicate a chromosome problem.
Nuchal translucency dating scan
During the screening, your doctor or a technician will take an abdominal ultrasound. You could alternatively have a transvaginal test, where an ultrasound probe is inserted through your vagina. An ultrasound uses high frequency sound waves to create an image from inside your body. They can then enter your age or date of birth in a computer program to calculate the risk of your baby having an abnormality.
An NT scan cannot diagnose Down syndrome or any other chromosome abnormality.
The test only predicts the risk. Talk to your doctor about available blood tests. As with any prediction, the accuracy rate varies. If you combine an NT scan with blood testing, the screening is about 85 percent accurate for predicting the risk of Down syndrome. No special preparation is required for an NT scan. In most cases, testing is completed in about 30 minutes. The ultrasound pictures may be easier to read if you have a full bladder, so your doctor may recommend drinking water about one hour before your appointment.
There are a number of tests and scans available to you during your pregnancy. The nuchal translucency scan is an ultrasound that may detect the risk of a number of chromosomal abnormalities.
A nuchal translucency scan is part of the ultrasound scan that most pregnant women have at around 12 weeks of pregnancy. The results of a nuchal translucency scan may tell you if your baby has a high or low risk of a chromosomal abnormality. Examples of chromosomal abnormalities include trisomy 21 Down Syndrometrisomy 18 Edwards Syndrome or trisomy 13 Patau syndrome.
The results will tell you if your baby is at high risk or low risk of chromosomal abnormality in comparison to the general population. The nuchal translucency scan is done between 11 and 14 weeks of pregnancy.
Usually the scan is done through your abdomen but occasionally the nuchal translucency can only be seen by inserting a probe into the vagina. You might also be offered a blood test around this time.
This is sometimes called a nuchal translucency scan. The nuchal translucency measurement can be taken during the dating scan. If you have agreed to have screening for Down's syndrome, the dating scan and the screening will usually happen at the same time. Find out more about the combined screening test for Down's syndrome. You will not be. The nuchal translucency screening is a normal ultrasound. You'll lie on your back while a technician holds a probe against your belly. It will take between 20 to 40 butterfishny.com: R. Morgan Griffin. The nuchal translucency scan (also called the NT scan) uses ultrasound to assess your developing baby's risk of having Down syndrome (DS) and some other chromosomal abnormalities, as well as major congenital heart problems. The NT scan measures the clear (translucent) space in the tissue at the back of your baby's neck.
Your doctor can look at the results of the combined test blood test and nuchal translucency scan to get a more accurate picture of the risk of a chromosomal abnormality. The results of the nuchal translucency scan will not be used alone to calculate the risk of a chromosomal abnormality. All your first trimester screening is combined to calculate your risk.
Diagnosis of Down Syndrome
If your risk is less than 1 inyou are considered low risk. If it is between 1 in 50 and 1 in you are considered intermediate risk.
If it is greater than 1 in 50 you are considered high risk. You may be referred to a genetic counsellor. They will discuss your options and help you to decide if you would like to have a more invasive diagnostic test, such as chorionic villus sampling CVS or amniocentesis.
Apr 04, An NT scan is a common screening test that occurs during the first trimester of pregnancy. This test measures the size of the clear tissue, called the nuchal translucency, at the back of your baby. Generally, your sonographer will be able to conduct the dating and nuchal translucency measurements at the same appointment, but if it is too early to get a clear image for the nuchal translucency then you will be asked to return at a later date. Your scan will also confirm that the baby's heart is beating normally. Getting a nuchal scan. All pregnant women will be routinely offered the nuchal translucency scan as part of their antenatal care. The scan needs to be done between 10 weeks and 13 weeks plus six days gestation, so many hospitals will include the test as part of your week butterfishny.com is up to you whether you want to have it.
These diagnostic tests can tell you definitively if your baby has a chromosomal abnormality or not. Tests such as CVS and amniocentesis carry a small risk of miscarriage.
Nuchal translucency scan (NT scan)
You might choose to have a nuchal translucency scan or you may choose to go straight to one of the more invasive diagnostic tests instead to get a definitive answer. You can have chorionic villus sampling from 11 weeks of pregnancy, or you can have an amniocentesis from 15 weeks of pregnancy. You can also call Pregnancy, Birth and Baby on to talk about these tests and what the results could mean for you and your pregnancy. Last reviewed: March InsideRadiology provides free and easily accessible, accurate, up to date and credible information about medical imaging tests and procedures.
Nuchal translucency is the name for the normal fluid space behind the neck of a foetus (unborn baby) that can be seen on ultrasound scans. A nuchal translucency scan (also called first trimester of pregnancy screening) is carried out during weeks of a pregnancy. The scan uses ultrasound to screen for Down syndrome, or other chromosomal. How is the nuchal scan performed? An NT scan must take place at a particular time in your pregnancy. This is between 11 weeks and 13 weeks plus six days, to be exact (NICE ), or when your baby's crown rump length (CRL) is between 45mm (in) and 84mm (in). So the NT scan will usually happen alongside your routine dating scan. The nuchal translucency scan is done between 11 and 14 weeks of pregnancy. It might need to be done alone, or it might be able to be done while you're having your dating scan. Usually the scan is done through your abdomen but occasionally the nuchal translucency can only be seen by inserting a probe into the vagina.