3 - Obs - Screening tests - Methods of Prenatal testing for Congenital Abnormalities

Question 1

Maternal Blood testing - what for NTDs?
levels of these blood markers: hCG, AFP, PAPP-A, oestriol, inhibin A, beta subunit b-hCG - altered show what?
results of these tests are combined with what 2 other things to screen for T21, 18, 13?

Answer 1

AFP - fetal liver product - raised
Chromosomal abs eg downs
other RFs - maternal age + USS measurements

Question 2

Fetal MRI - used in Dx of ? lesions - better at diff ? tissues eg liver and lung

3D/4D USS - 3d or ?-? 3D (4D) USS - allows better evaluation of certain abnormalities - where mostly used?

Answer 2

intracranial
soft

real time
tertiary centres

Question 3

Amniocentesis - diagnostic or screening test?

• removal of amniotic fluid using what?
• when safest?
• 1% of women ? afterwards.
• enables Dx of ? abnormalities, some infections eg ? and ? , and ?disorders eg SCA and CF

Answer 3

diagnostic
fine gauge needle under USS guidance
safest from 15w
miscarry 
chromosomal
CMV and Toxo
inherited

Question 4

Chorionic Villus Sampling - ?test, ? of trophoblast, fine gauge needle through abdo wall/? into placenta, after ?wks. Result faster than ?, and allows ? fetus to be identified. Miscarriage rate slightly ? than amnio, due to being ? , when ? miscarriage more common, and more ?procedure. Used to diagnose ? probs and ? dom and recessive conditions.
With amnio and CVS, ? and ?both used to diagnose most common things in <48h.

Answer 4

diagnostic
biopsy
cervix
11w
amnio
abnormal
higher
earlier
spont
difficult
chromo
autosomal
FISH and PCR

Question 5

USS - first trimester - used to exclude ? pregnancy - asses pregnancy ?, and detect any ? ? of conception after ?
Also, at 9-12w used to estimate ? ? by measuring ?-? length
Can detect ? pregnancy
Screens for chromo abs using ? ? and diagnoses ? abns

Answer 5

ectopic
viability
retained products
miscarriage
gest age
crown-rump
multiple
nuchal translucency
structural

Question 6

USS - second trimester

• diagnosis of ? abns, screening for ? abns
• Help other diagnostic (eg ?) or therapeutic (eg ?) techniques
• ? for fetal assessment or of ? arteries.

Answer 6

structural
chromo
amnio
transfusion
doppler
uterine

Question 7

USS- 3rd trimester

• assessment of fetal ? - diagnosis of placenta ?
• determining ? in difficult cases
• doppler for fetal assessment

Answer 7

growth
praevia
presentation

Question 8

Some abnormalities only seen later in preg - do USS if ?, ?, or suspected intrauterine ? ?

Answer 8

breech
polyhydraminos
growth restriction