Fetal Medicine Flashcards
What infection causes laryngeal papillomas of the neonate
HPV 6 & 11 - genital warts
A triad of cardiac, eye and ear symptoms is caused by which congenital infection
Rubella
Cardiac - patent ductus, pulmonary valvular stenosis, coarctation of the aorta, ASD, VSD
Eye - congenital cataract
Ear- sensorineural deafness
How long after presentation with varicella should a fetal USS be done
5 weeks
Describe Holoprosencephaly
What is it associated with
Forebrain fails to develop into two hemispheres
Other features: fused thalami or ventricles, absence of cavum septi pellucidi, dysgenesis of the corpus callosum
Trisomy 13, 18, triploidy and warfarin
What % of pregnancies are found to have major structural anomalies
2-3%
What % of neonatal deaths are due to congenital malformations
20-30%
What is the detection rate of serious cardiac anomalies at the anomaly scan
50%
When should the anomaly scan be completed
18-20+6
How common is anencephaly
1:1000
What is an encephalocele
Herniation of intracranial content through defect in the skull
75% are occipital
At what gestation is inability to see the bladder abnormal
14 weeks
What % of megacystitis resolve if the karyotype is normal
90%
A NT measurement of more than what is associated with an increased risk of fetal chromosomal anomalies
3.5mm
What is the probability of pulmonary hypoplasia if prom occurs at 21 weeks
90%
Regarding anencephaly what is the risk of recurrence
2-3%
Define ventriculomegaly
Lateral ventricles >10mm
What are the features of spins bifida noted in the brain
Lemon shaped skull
Banana cerebellum
Arnold chiari malformation
Enlarged lateral ventricles
Describe the features of dandy walker malformation and associations
Congenital absence of the cerebellum vermis
Associated chromosomal and genetic abnormalities
Regarding spina bifida
What is the risk of recurrence after 1, 2 & 3 affected pregnancies
5% after one affected pregnancy
12% after two affected pregnancies
20% after three affected pregnancies
Regarding fetal anomalies name the condition
a-FP normal
Associated genitourinary and gastrointestinal abnormalities
Strong association with maternal diabetes
Sacral agenesis
In what context are choroid plexus cysts relevant
In the context of other fetal anomalies, the risk of trisomy 18 is 1:2
Regarding fetal anomalies name the condition
Bilateral talipes and polyhydramnios
Congenital myotonic dystrophy
Cardiac disease accounts for what % of deaths secondary to congenital disease
35%
What is the risk of congenital cardiac anomaly with NT >3.5mm and a normal karyotype
6%
What is the risk of having congenital cardiac anomaly if
One previous child affected
2%
What is the risk of having congenital cardiac anomaly if
2 previous children affected
10%
What is the risk of having congenital cardiac anomaly if
Mother has congenital heart disease
6%
What is the risk of having congenital cardiac anomaly if
Father has congenital heart disease
2%
Is there always oligohydramnios with bilateral renal agenesis
No liquor volumes may be normal in 1st trimester scan as fetal urine contributes less early
If unilateral prognosis is good, if bilateral lethal
What is the management if renal pelvic dilatation when diagnosed at anomaly scan
Repeat scan 28-32 weeks and neonatal follow up
How often is multicystic dysplastic kidney bilateral
If bilateral what is the prognosis
1:15
Lethal if bilateral
What is the risk of trisomy 21 if double bubble sign seen
30%
Double bubble - duodenal atresia
What are the anomalies in the VACTERL acronym
Vertebral Anal atresia Cardiothoracic Tracheo-Oesophageal fistula Eosophageal atresia Renal Limb
Regarding Exomphalos
What % is associated with other abnormalities
What are these abnormalities and in what % of cases are they found
70-80% associated anomalies
50% cardiac
30% trisomy - 13,18 and 21
10% beckwith wiedeman syndrome
What %are offered invasive testing annually
5%
When is amniocentesis carried out
Mainly >15/40
Early <15/40
When is CVS carries out
11-13+6
Risk of miscarriage may be slightly higher than amnio after 15/40
What is the additional risk of miscarriage with amniocentesis
When is the risk higher
1%
Risk higher if performed < 15 weeks
Regarding twins and invasive testing
If monochorionic and amniocentesis performed, how many sacs should be sampled
One
Regarding twins and invasive testing
If dichorionic what are the concerns with CVS
High risk of contamination of chorionic tissue - false + or false -
Regarding HIV and invasive testing
What are the risks and how can they be reduced
Low if early pregnancy and low viral load on treatment
Should delay till treatment started and viral load reduced
Regarding Hep B and invasive testing
What factors impact risk of transmission
Maternal viral load, risk of transmission overall thought to be low
