Lecture 4A p2 Flashcards
How is yolk sac measured
Inner to inner ap measurement
Usual shape of yolk sac
Circular
Max diameter of YS is _____mm visualized by wekk _____
5.6 mm
10 weeks
Yolk sac is very important in
Early embryo development
Functions of the yolk sac (3)
Providing nutrients to early embryo
Vitelline duct connect YS to embyro
Production of albumin, AFP and other proteins
Embryonic hematopoiesis
Wher does hematopoiesis continue after the yolk sac?
Liver in 8th week
The yolk sac will lose function as
The placenta takes over
Week 6-10 embryo is aka
Fetal pole
At 6 weeks embryo appears ______ to the yolk sac
Adjacent
Embyro is ____-_____mm when first visualized
2-4mm
what is Crown rump length (CRL)
Main measurement used in first trimester
Most accurate estimate of gestational age
CRL is length of
Embryo or fetus from top of its head (crown) to bottom (rump)
CRL measurement should not include
Yolk sac or extremities
Is CRL used in 2nd trimester
No
Embryo CRL 6.5 weeks
5mm
Embryo CRL 7-8 weeks
11-16mm
Embryo CRL 8-9 weeks
17-23
Embryo CRL 9-10 weeks
23-32mm
What may be seen at 8-9 weeks
Limb buds
What may be seen by week 9-10
Movement
Firest organ to function in the embryo
Primitive heart
The primitive heart begins to pump at ____ weeks
5
Cardiac activity can be seen on embryo >____mm
> 5mm
Cardiac activity must be seen if fetal pole = _____mm
7mm
BPM 5 WEEKS
100-115 BPM
9 WEEKS BPM
170-180BPM
Bpm DECREASES soon after
160-170
2nd and 3rd trimeter bpm
110-160
