Week 3

Question 1

What other factors can genetic screening test for?

Answer 1

Other chromosomal anomalies.

An increased nuchal translucency is also a powerful marker for cardiac anomalies, other structural anomalies, and genetic syndromes.

Increased nuchal translucency have an increased risk of adverse pregnancy outcome, such as fetal loss and developmental delay

Question 2

What are the two most common features of normal anatomy in the first trimester that can lead to a misdiagnosis of pathology?

Answer 2

• Intracranial cystic structures
• Physiological anterior abdominal wall herniation

Question 3

What is chorionic villus sampling(CVS) or amniocentesis?

Answer 3

CVS- 1st trimester test (10-13weeks). Used for fetal karyotyping and gene analysis.

Amnio- performed between 15-17weeks. Most common invasive technique where amniotic fluid is taken transabdominally from the amniotic sac.

Question 4

What is pre-eclampsia and why is it important?

Answer 4

Pre-eclampsia is a pregnancy-specific condition characterised by hypertension occurring after 20weeks gestation.

The cause of pre-eclampsia is multifactorial, with impaired placentation being a predominant factor. If left untreated, it may lead to preterm birth, intrauterine growth restriction, and placental abruption. To determine the risk of early onset pre-eclampsia, uterine artery Doppler is implemented, to evaluate blood flow in the uterine arteries that supply the placenta.

Question 5

How do you deal with a situation where cord crosses the nuchal translucency and causes a focal narrowing?

Answer 5

When the cord crosses the NT causing focal narrowing, a measurement of the max size on either side of the narrowing should be taken. The average should be calculated as the final measurement. This does not apply if the narrowing is quite lateral on the NT.

Question 6

What is NT and why is it important?

Answer 6

Nuchal translucency is the normal subcutaneous space, between the skin and the cervical spine.

Measurement is performed to determine the risk of chromosomal abnormality. Increased
NT (>3mm) is the best indicator of aneuploidy, particularly T21, in an otherwise normal fetus.

Increased nuchal translucency on its own is not an abnormality. It is an indicator
of ‘risk’ only.

Question 7

What is NIPT??

Answer 7

Non- Invasie prenatal testing.

• maternal blood test looking for fetal DNA in maternal plasma.

Question 8

What other associations can increase NT suggest?

Answer 8

• wide range of fetal structural abnormalities
• major defects of the heart and great arteries
• wide range of skeletal dysplasia
• other genetic syndromes

Question 9

What other markers are commonly integrated with NT

Answer 9

• nasal bone
• ductus venosus
• tricuspid regurgitation