Antenatal diagnosis Flashcards
What are the main diagnostic techniques in antenatal diagnosis?
Maternal Serum Screening
Detailed US scans
What are more specialised antenatal diagnostic techniques?
Chorionic Villous Sampling
Foetal blood sampling
Amniocentesis
Non Invasive Pre Natal Testing
Why is antenatal screening useful?
Allows:
o Reassurance where disorders not detected
o Optimal obstetric management of mother and fetus
o Interventions for a limited number of fetal conditions, such as relieving
bladder obstruction or draining pleural effusions to improve perinatal outcome
o Counselling and neonatal management to be planned in advance
o Option of termination of pregnancy to be offered for severe disorders affecting
fetus, or comprising maternal health
What infections can be found in maternal blood?
Hep B
Syphilis
Rubella
HIV
What non infectious pathologies can be found in maternal blood?
Blood group/ Rhesus/ Ab incompatibilities
Neural tube defects (maternal serum alphafetoprotein)
Down’s syndrome (screening age, biochemistry, US nuchal translucency - if high then fetal chromosomal analysis)
What can be determined on US?
Gestational Age Multiple pregnancy Structural malformations Foetal growth Amniotic fuid volume Polyhydramnios
After an amiocentesis, how can the fluid be analysed?
Chromosome/ micro array and DNA analysis
PCR (foetal infection)
What can we do with foetal blood sampling?
Foetal:
Hb
infection serology
blood transfusion
What can we do with chorionic villous sampling?
Chromosome/ micro array and DNA analysis
PCR (foetal infection)
Enzyme analysis of inborn errors of metabolism
What can you do with PGD?
Genetic analysis of cells from developing embryo in IVF
What is foetoscopy?
Minimally invasive surgery (e.g. laser photocoagulation of communication vessels in twin twin transfusion syndrome)
What can you used NI genetic diagnosis for?
Identification of foetal gender and rhesus status
