Module 4&5 - Maternal Testing & Screening

11-14w

When does the 1st trimester screen occur

19-20w

When does the 2nd trimester detailed anatomy scan occur

Fetal assessment scan

What does FAS stand for

Non-invasive prenatal testing

What does NIPT stand for

After 10weeks

When does the NIPT occur

Cell-fee DNA in maternal plasma

What does NIPT test

>99%

What is the detection rate of NIPT

Increased BMI

What may decrease the accuracy of the NIPT

78%

What is the detection rate of the NIPT when the mother is 300lbs

Trisomy 21, 18, 13

What does NIPT stand for

Low-risk and high-risk

What are the two results that can come back from NIPT

False

T/F: NIPT is converse by Alberta health

First trimester screen

What does FTS stand for

11-14 weeks

When does a FTS occur

NT, B-hCG, PAPP-A, and maternal age

What does the FTS combine in its testing

Trisomy 13, 18, 21

What does the FTS screen for

Subcutaneous fluid collection under the skin behind the fetal neck

What is the nuchal translucency and where is it located

Increases

NT ______________ with CRL

Chromosomal abnormalities cardiac defects, genetic disorders

What is increases NT thickness associated with

Noonan syndrome

What is the most common genetic disorder associated with an increased NT

Nuchal fluid begins to increase, can appreciate other anatomy, the abdominal hernia see at 8-10 weeks should start to resolve

Explain why we look at the NT at 11 weeks

Increase in false negatives after this point

Why do we stop looking at the NT after 14 weeks

80%

What is the detection rate of trisomy 21 with the NT alone

82%-87%

What is the detection rate of trisomy 21 with all tests included in the FTS

11-14 weeks

What must the gestational age be for the nuchal translucency scan

45-84mm

What must the CRL be for the NT scan

Gains turned down, widest translucency measured, neutral position

Describe the scanning technique for the NT

1

Which is the NT

NT

What is 1

Occipital bone

What is 2

Nasal bone

What is 3

Palate

What is 4

Mandible

What is 5

Thalami

What is 6

Midbrain

What is 7

Inner to inner

What is the correct calliper placement for the NT mmt

False

T/F: you can still measure the NT even is you can't see the amnion under it

Brain stem

What is 8

Medulla oblongata

What is 9

4th ventricle

What is 10

Choroid plexus of 4th ventricle

What is 11

1st one

Which is the correct calliper placement for the NT

Zygotmatic arch

What is the teal arrow pointing to

Mean you aren't mid sagittal and need to adjust your angle

What does it mean if you see the zygomatic arch in the image

Normal

Visually estimating, does this NT look normal or thick

Thick

Visually estimating, does this NT look normal or thick

95%

What is the detection rate of trisomy 18 and 13 with FTS

Increased maternal age, increased fetal NT, decreased PAPP-A

What are all three trisomy's associated with

Increased

In trisomy 21, B-hCG is ______________

Decreased

In trisomy 13 & 18, B-hCG is ____________

B-hCG decreases and PAPP-A increases with gestation

Describe the increase/decrease of B-hCG and PAPP-A with normal pregnancy

11weeks

When do you start to see the nasal bone

Yes

Can you see the nasal bone in this picture

No, just a skin line

Can you see the nasal bone in this picture

60-70%

What percentage of fetuses with trisomy 21 have a hypoplastic nasal bone

50%

What percentage of fetuses with trisomy 18 have a hypoplastic nasal bone

30%

What percentage of fetuses with trisomy 13 have a hypoplastic nasal bone

Turner's syndrome

What does cystic hygroma indicate

Persistence of mid-gut herniation

What is omphalocle

Omphalocle, anechphaly, alobar holoprosencephaly, cystic hygroma, megacystis

What other abnormalities can be seen at the 11-14 week scan

Trisomy 13 and 18

What may megacystis indicate

Trisomy 13

What does alobar holoprosencephaly indicate

Alobar holoprosencephaly, facial defects, microcephaly, micronathia, VSD

What findings may indicate trisomy 13

True

T/F: trisomy 13 is associated with a high detection rate because it has a lot of unique indications on ultrasound

Reversed A wave in the DV and TR

What Doppler findings may indicate trisomy 21

False

T/F: the risk of turners and triploidy increase with maternal age

Uterine artery Doppler, PAPP-A

What is used to screen for preeclampsia

Low

Is PAPP-A is ______ it is considered a marker for preeclampsia

Dicrotic notch and low diastolic blood flow

What abnormal signs are you looking for in the uterine artery Doppler

Normal

Is the spectral of the uterine artery on the top normal or abnormal

Abnormal

Is the spectral of the uterine artery on the top normal or abnormal

Prophylactic use of daily aspirin

How are those identified as high risk for preterm PE treated

False, only early or preterm PE

T/F: aspirin is successful in preventing both preterm (<37 weeks) and term PE (>37 weeks)

150bpm

What is the normal FHR at 14w

Trisomy 18 or tripleuoidy

What can bradycardia indicate

Turner's syndrome or trisomy 13

What can tachycardia indicate

170bpm

What is considered tachycardic at 14 weeks

Measure again later, baby may just be active

What should you do if you find a baby with a very high heart rate to confirm the finding

15 and 20 weeks

When is the triple screen performed

MS-AFP, uE3, B-hCG

What are the 3 things testes in the triple screen test

Maternal serum alpha feta protein

What is MS-AFP

Unconjugated estriol

What is uE3

70%

What is the detection rate of the triple screen

Trisomy 21 and 18, other chromosomal abnormalities

What does the triple screen detected

No

Can the triple screen detect trisomy 13

Fetal liver

What is AFP mainly produced by

Yolk sac, GI tract, kidneys, placenta

What else is AFP produced by

True

T/F: AFP crosses the placenta into maternal circulation

True

T/F: MSAFP and amniotic fluid AFP levels change with gestational age

>2.5 times the mean

What MSAFP value is suspicious for birth defects and multiples

Wrong date

What is the most common cause of abnormla levels of MSAFP

Multiples, fetal Demi's, fetal abnormality

What else can abnormal MSAFP levels be from

Sensitive, not specific

Is MSAFP levels sensitive or specific, or both

trisomy 21 and 18

What does decreased MSAFP relate to

Neural tube defect (NTD)

What is the most common cause of increased MSAFP Q

Omphalocele, gastroschisis, congenital renal disease, esophageal atresia

What else may increases MSAFP levels be related to

Trophoblasts

What is B-hCG produced by

Trisomy 21, multiples, molar pregnancy, wrong dates

What is increased B-hCG levels related to

Trisomy 18

What is decreases B-hCG levels related to

Fetal adrenal glands and liver

What produces and synthesizes uE3