Prenatal Diagnostic Testing

Question 1

Quad screen

Answer 1

AFP, estriol, inhibin A, B-HCG

Question 2

Trisomy 21 quad results

Answer 2

Up: inhibin A, B-HCG
Down: MSAFP, estriol

Question 3

Quad screening

Answer 3

AFP, Estriol, Inhibin A, B-HCG

Done in weeks 15-22

Question 4

Trisomy 21 Quad Screen results

Answer 4

Up: inhibin A, B-HCG
Down: AFP, estriol

Question 5

Trisomy 18 quad screen results

Answer 5

Everything down

Question 6

Elevated AFP

Answer 6

Neural tube defects: anencephaly, spina bifida
Abdominal wall defects: gastroschisis, omphalocele
Wrong GA, multiple gestations, fetal death, placental abnormalities

Question 7

Low AFP

Answer 7

Trisomy 21 and 18
Fetal demise
Incorrect GA

Question 8

PAPP-A

Answer 8

Pregnancy associated plasma protein A
Weeks 9-15
PAPP-A + nuchal translucency + B-HCG = 91% sensitive for Trisomy 21 and 95% sensitive for Trisomy 18
Benefits: can do before CVS

Question 9

Amnio results for lung maturity

Answer 9

lecithin:sphingomyelin ratio > 2.5 OR

presence of phosphatidylglycerol