What is a normal nuchal fold measurement?
The nuchal fold is a normal fold of skin at the back of a baby’s neck. This can be measured between 15 to 22 weeks in pregnancy as part of a routine prenatal ultrasound. Follow-up is offered when the nuchal fold is thick (6 mm or more). Many healthy babies have thick nuchal folds.
What is a normal NT measurement at 12 weeks?
First trimester measurement of NT at 12 weeks of gestation was 3.2 mm during the routine first trimester screening. The normal range of NT for this age is 1.1-3 mm.
What is a normal nuchal fold measurement at 20 weeks?
The generally accepted upper limit for nuchal fold thickness up to 20 weeks’ gestation is 6 mm. Some authors have suggested that decreasing the cutoff to define a thick nuchal fold to 5 mm would increase the sensitivity for detection of trisomy 21.
What is a normal nuchal translucency measurement at 10 weeks?
Results: The median nuchal translucency measurement increased from 0.7 mm at 10 weeks’ gestation to 1.5 mm at 13 weeks. A nuchal translucency measurement greater than 2.5 mm was found in 4.6% of the fetuses at 10 weeks’ gestation; the incidence increased to 8.7% at 14 weeks.
What is an abnormal nuchal fold measurement?
ACOG defines an abnormal nuchal fold as ≥ 6mm in the 2nd trimester (typically performed between 15w0d and 22w6d). The SOGC (Society of Obstetricians and Gynecologists of Canada) considers a nuchal fold to be abnormal when the measurement is ≥ 5 mm at 16-18 weeks, or ≥ to 6 mm at 18 to 24 weeks.
What is a low risk NT measurement?
Getting the results of my NT scan For a baby that is between 45 mm and 84 mm in size, an NT of less than 3.5mm is considered normal. An NT less than 1.3 mm is considered to be low-chance and an NT of 6 is considered high chance for Down’s syndrome and other potential chromosomal abnormalities.
Is 1.2 mm nuchal translucency good?
A baby with an NT of 1.3mm is within the normal range. The baby with an NT of 2.9mm is also within the limit of normal range. As the NT increases, so does the chance of Down’s syndrome and other chromosomal conditions.
Does a thick nuchal fold mean Down syndrome?
Many studies have shown that a thickened nuchal fold in a second-trimester fetus is a sonographic sign suggestive of a high risk for Down syndrome. These series have included fetuses already at risk for aneuploidy because of advanced maternal age or abnormal maternal serum alpha-fetoprotein (AFP) levels.
What are soft markers for Down syndrome?
The most commonly studied soft markers of aneuploidy include a thickened nuchal fold, long bones shortening, mild fetal pyelectasis, echogenic bowel, echogenic intracardiac focus, FMF angle > 90 degrees, pathologic velocity of Ductus venosus and choroid plexus cyst.
What is a high nuchal fold measurement?
What is considered a high risk for Down syndrome?
Patients are more likely to have a baby with Down syndrome or another chromosome abnormality when they are age 35 or older, or if they have already had a child with such an abnormality. These patients are considered “high-risk” and have additional testing options.
What is abnormal nuchal translucency?
The fetal NT increases with gestational age/crown–rump length. Due to this the NT measurement may considered abnormal when it is above 3.0 mm, or above the 99th percentile for the gestational age. In pooled data from 30 studies, NT screening alone has a sensitivity for trisomy 21 of 77% with a 6% false-positive rate.
What is normal nuchal fold at 19 weeks?
What is an increased (thick) nuchal fold? The nuchal fold is a normal fold of skin at the back of a baby’s neck. This can be measured between 15 to 22 weeks in pregnancy as part of a routine prenatal ultrasound. Follow-up is offered when the nuchal fold is thick (6 mm or more). Many healthy babies have thick nuchal folds.
What does nuchal translucency measurement mean?
Nuchal Translucency. Fetal NT refers to the normal subcutaneous fluid-filled space between the back of the neck and the overlying skin.
What is a normal nuchal translucency?
What is a normal nuchal translucency measurement? An NT of less than 3.5mm is considered normal when your baby measures between 45mm (1.8in) and 84mm (3.3in) . Up to 14 weeks, your baby’s NT measurement usually increases as they grow. But after this, extra fluid can be reabsorbed.
How do they measure nuchal translucency?
Carrying out the ultrasound examination by appropriately trained sonographers.