1st Trimester Flashcards
linea terminalis
pubic symphisis to sacral prominatory
When will the first evidence of pregnancy be detected?
4.5 weeks gestational age
What is the first sign of pregnancy songraphically?
intra-decidual/gestational sac at 4.5-5 weeks gestational age
What is the first definative finding of an intrauterine pregnancy?
yolk sac at 5-6 weeks gestational age and a MSD of 8 mm
When is the embryo visualize on US?
6+ weeks and a MSD of 16 mm
What is MSD?
Mean Sac Diameter
What is the double decidual sac?
decidua vera and decidua capsularis (now debated)
What is required for IUP?
yolk sac or embryo
At what quant is a yolk sac usually seen?
5000 mlU/ml
The center of the yolk sac should be…
anechoic
Cardiac activity is usually seen by what crown rump length (CRL)?
5 mm
When should CRL not be used?
When the embryo can flex and extend
With CRL of <5 mm what should the HR be?
> 80-90 BRP
With CRL of >5 mm what shoud the HR be?
> 110 BPM
Verify in two planes that an IUP is surrounded by at least… of myometrium.
5 mm
What is the definitve diagnosis for preganancy failure?
embryo > 5mm without cardiac activity
Definitive sign of ectopic pregnancy
Gestational sac with yolk sac or embryo outside of uterine cavity
With free fluid in either cul de sac, where else should you look for fluid?
Morrison’s pouch
How can you distinguish interstitial ectopic from intrauterine?
thinning of myometrium around the pregnancy to less than 5 mm
