Your scan is performed by a sonographer/clinician trained in first-trimester screening and NT measurement standards.

There is very little preparation needed. You should have some fluid in the bladder but not be uncomfortably full. Drinking fluids prior to the examination will enlarge the bladder. The bladder is used as an acoustic window to improve the image quality and it also improves the position of the baby. It is a good idea to wear comfortable clothing that gives easy access to your lower abdominal area.

The scan is performed by applying a warm gel over the patient’s lower abdominal area. A transducer (a smooth handheld device) is moved gently across the abdomen with a sliding and rotation action to scan the baby through the tummy. It can sometimes be difficult to accurately measure the Nuchal Translucency because of the position of the fetus. In this case, the sonographer/radiographer will explain that a transvaginal ultrasound is needed and will request your permission to do so. A transvaginal ultrasound involves a small specially shaped transducer to be inserted into the vagina. Because the transducer is closer to the fetus it can provide clearer images.

There are no known risks to performing trans-abdominal ultrasound which uses sound waves to obtain pictures or images. There is no radiation involved. Nuchal Translucency testing is non-invasive and poses no risk to the foetus or similarly no risk to you or of miscarriage. Should you have First Trimester Screening (FTS)? Only you can decide whether or not to have FTS. To book a Nuchal Fold Scan please call (01) 663 5060 or use the Make a Booking online form. This scan is from 11 weeks to 14 weeks.

When the nuchal fold has a thickness of over 6 mm, the baby is considered to have a high chance of fetal abnormalities such as Down’s Syndrome, heart problems and other anomalies.

Usually, the nuchal fold grows in proportion to the developing baby. For example, when a baby measures between 45 to 84 mm (1.8 to 3.3 inches), a nuchal fold of under 3.5 mm would be considered to be within the normal range.

The nuchal translucency normally develops in proportion to the growing baby. 90% of babies with an NT measurement within the range of 2.5 mm to 3.5 mm will not develop Down’s Syndrome.

When the baby has reached 12 gestational weeks of pregnancy, the average range for nuchal thickness comes in at 2.18 mm. However, statistics have also revealed that 13% of babies who present with an NT of over 2.5 mm at 12 weeks are born chromosomally normal.

The nuchal translucency test is considered to be between 70% to 80% accurate. When performed along with an ultrasound and blood tests, the accuracy rises to between 80% to 90%.

The Harmony Test is a more accurate and non-invasive alternative.

The nuchal translucency test needs to be carried out between gestational weeks 11 to 14, as this is the period when the neck of the baby is still transparent.

Trisomy 21 is the more common version of Down’s Syndrome. This is when people have 47 chromosomes er cell, as opposed to 46. Trisomy 21 occurs when nondisjunction takes place – this is an error in how the cells divide.

The best way to try to prevent Down’s Syndrome is by planning ahead before conception. Taking 400 mcg (micrograms) of folic acid each day ideally for a few months before conception. Then you need to continue to take in during your early pregnancy.

Each woman will be given an estimate of her individual risk for their pregnancy. Your risk is assessed by taking into account the following:

Age of the mother – Amount of fluid behind the neck of the fetus (nuchal translucency).

Fetuses at risk of Down Syndrome tend to have a higher amount of fluid around the neck. Babies accumulate fluid at the back of their neck (nuchal) during the first trimester. As a result of this fluid, the baby’s nuchal fold increases in thickness each day of gestation until the fluid disappears around the 15th week. Researchers have established an average or “normal” thickness for each day during the three weeks you are eligible for the screening If your baby’s nuchal fold is thicker than average, he or she is considered at a higher risk for an abnormality; if it’s thinner, his or her risk is lower.

A more accurate risk assessment combines the Nuchal Translucency scan with the results from two bloods tests that measure the levels of pregnancy-associated plasma protein-A (PAPP-A) and human chorionic gonadotrophin (hCG) in the mother’s blood. Abnormal levels of these two pregnancy-related substances may indicate a problem. Combining the scan and blood test gives a more accurate result than either the ultrasound part or the blood part of the test done on their own.

You must be at least 10 weeks gestation or more for the blood sample to be taken. The Nuchal Translucency scan cannot tell for certain if your baby has a chromosonal defect, however, it can help you decide whether or not the chance of your baby having a chromosonal problem is high enough to warrant having an invasive test such as CVS (Chorionic Villus Sampling) or Amniocentesis. However, these tests carry a slight chance of miscarriage and therefore options should be discussed with their healthcare professional. CVS is performed in the 13th week and amniocentesis around 15th or 16th week of pregnancy.