First Trimester
Name 3 indications for a first trimester USS?
Uncertain about gestation or LMP
Bleeding or pain
Suspicion of multiple pregnancy
First trimester screening
What is the most common reason for second trimester USS?
Morphology
Placental position
Cervical length
In which instances is a bedside USS indicated?
Fetal presentation prior to C/S
Fetal presentation prior to IOL
Fetal presentation prior to instrumental birth
Fetal heart rate confirmation
Name 3 pieces of information a Nuchal Translucency Screen provides?
NT measurement
Presence of a nasal bone
Angiogenic biomarkers
Risk for Trisomy 13, 18 and 21
What is considered a shortened cervical length at Morphology USS?
Transabdominal >35mm
Transvaginal >25mm
What is the minimum recommendation for documentation of USS?
eMaternity
Reports to be scanned to EMR
At what gestation range, can a NTS be done?
12 to 13+6 weeks
For which conditions should you recommend the Morphology USS be attended at a specialist women's USS center?
Increased NT at FTS
Type 1 or 2 diabetes
Previous baby with fetal abnormality
Exposure to potential teratogens
Presence of maternal congenital conditions
When should you plot USS assessments on the NSW Health Fetal Biometry Ultrasound Growth Scan Chart?
When serial USS has been ordered
Where growth is not following the appropriate trajectory
OR
AC or EFW drop of 50 centiles
What is the most accurate gestational range for accuracy of a dating USS?
8-12 weeks
Name 5 further indications for second and third trimester USS.
Women unsuitable for serial SFH
Multiple pregnancy
Discrepancy >3cm between gestation and FH
Uterine fibroids >10cm in size
Previous shoulder dystocia requiring maneuvers
Placenta previa or low-lying placenta
Maternal antibodies
Name 4 indicators for escalation of results.
Any fetal or uterine abnormality
Placenta is <2cm form cervical os
Abnormal doppler
SGA <10th percentile
AFI <8 and >25
High risk for fetal aneuploidies
Cervical length <35mm on TA and 25mm on TV USS
What further testing would you arrange when the NTS reports increased risk for Trisomy 13, 18 or 21?
NIPT
Amniocentesis
CVS
When might a woman be referred for fetal Echocardiogram? (Up to 6)
Previous baby, maternal or paternal history of congenital heart disease
Pre-gestational diabetes with HbA1c >7%
Maternal exposure to teratogens
NT measurement of >3.5mm after genetic testing
Suspected cardiac structural anomaly at morph or any other USS
Inability to obtain cardiac views at morph despite repeated attempts
How often is USS indicated in a twin pregnancy?
MCDA 16 weeks, Morphology, 24 weeks then every 2 weeks
DCDA 16 weeks, Morphology then every 4 weeks