What should the nuchal fold be at 20 weeks?

What should the nuchal fold be 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 an abnormal nuchal fold?

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.

Can nuchal thickness decrease?

Conclusion: In fetuses with abnormal karyotype, the second nuchal translucency measurement tends to be increased or unchanged, while in normal cases the size of nuchal translucency is generally reduced.

What happens if NT value is high?

An increased NT has also been associated with a high risk of miscarriage or fetal death. This risk increases with increasing NT thickness, and miscarriage or fetal death may be preceded by cardiac failure symptoms such as fetal hydrops.

How many mm should nuchal fold be?

The normal range of NT for this age is 1.6-2.4 mm. Nuchal skin fold (NF) measurements and prenatal follow-up ultrasound findings were normal. A Triple test was performed, and it showed a positive result and a high risk of trisomy 21.

Can a healthy baby have a thick nuchal fold?

Many healthy babies have thick nuchal folds. However, there is a higher chance for Down syndrome or other chromosome conditions when the nuchal fold is thick. There may also be a higher chance for rare genetic conditions.

What causes thick nuchal fold?

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.

Can nuchal translucency go away?

Studies have shown that in normal fetuses the fluid collection known as NT increases with gestational age until about 13 weeks’ gestation3 and usually disappears after 14 weeks3, 4.

Can increased NT resolve?

Occasionally, there are cases exhibiting markedly increased NT which resolve spontaneously within 10–14 weeks of gestation (Pajkrt et al., 1995; Fukada et al., 1997).

Can nuchal translucency be wrong?

An abnormal result on the nuchal translucency or combined screening test doesn’t mean that your baby has a chromosomal abnormality. They just mean that there’s a statistical likelihood of having a problem. That’s why your doctor will suggest follow-up diagnostic testing. Try not to overthink your results.

How common is a thick nuchal fold?

According to the practice bulletin concerning fetal aneuploidy screening published by the American Congress of Obstetricians and Gynecologists, the likely ratio (LR) for thickened nuchal fold (TNF) is 11 to 18.6.

What is the cut off for nuchal translucency?

Objectives: An association between isolated, increased nuchal translucency thickness (NT) and pathogenic findings on chromosomal microarray analysis (CMA) has been reported. A recent meta-analysis reported that most studies use a NT cut-off value of 3.5 mm.

Is it normal to have a thick nuchal fold at 14 weeks?

A nuchal skin fold thickness of � 6 mm is considered abnormal between 14 and 21 weeks. Excess skin along the back of the neck is well known in babies with Down syndrome (80\% of neonates). There are many studies that have reported the relationship of a thickened nuchal fold with abnormal karyotypes.

What is the normal thickness of the nuchal skin fold?

This nuchal skin fold increases with advancing gestational age and ranges between 1 and 5 mm in normal fetuses between 14 and 21 weeks gestation. A nuchal skin fold thickness of � 6 mm is considered abnormal between 14 and 21 weeks. Excess skin along the back of the neck is well known in babies with Down syndrome (80\% of neonates).

How do you thicken the nuchal fold?

Nuchal fold can be spuriously thickened by angling caudally (intersecting the inferior level of the cerebellum and occiput). This nuchal skin fold increases with advancing gestational age and ranges between 1 and 5 mm in normal fetuses between 14 and 21 weeks gestation.

What is the normal range of nuchal skin fold during pregnancy?

This nuchal skin fold increases with advancing gestational age and ranges between 1 and 5 mm in normal fetuses between 14 and 21 weeks gestation.