Week 5

Question 1

All women should have first trimester scan between

Answer 1

7-13+6 week

Question 2

Early first trimester:

Answer 2

confirm viability,
* establish gestational age accurately,
* determine the number of fetuses

Question 3

Multiple pregnancy:

Answer 3

assess chorionicity and amnionicity.

Question 4

Late first trimester

Answer 4

1 – 14 week

confirm viability,
* establish gestational age accurately,
* determine the number of fetuses and chorionicity
and amnionicity in cases of multiple pregnancy
* detect major fetal abnormalities (basic fetal
anatomy)
* placental appearance and location
* amniotic fluid volume.
* aneuploidy screening, to measure the nuchal
translucency (NT) thickness.

Question 5

DOUBLE DECIDUAL SIGN

Answer 5

INTERFACE BETWEEN THE DECIDUA CAPSULARIS AND
THE DECIDUA PARIETALIS BEFORE THEY FUSE.
*USEFUL SIGN OF A VIABLE GESTATION PRIOR TO OBSERVATION OF
GESTATIONAL SAC
* EVIDENT IN 50% OF PREGNANCIES

Question 6

FERTILIZATION TAKES PLACE HOURS AFTER OVULATION IN THE
AMPULLA PORTION OF THE TUBE
IS THE TERM USED TO DEFINE A FERTILIZED OVUM (THE FIRST
DIPLOID CELL)

Answer 6

FERTILIZATION TAKES PLACE 24 TO 36 HOURS AFTER OVULATION IN THE
AMPULLA PORTION OF THE TUBE
*ZYGOTE IS THE TERM USED TO DEFINE A FERTILIZED OVUM (THE FIRST
DIPLOID CELL)

Question 7

FIRST SONOGRAPHIC
EVIDENCE OF AN IUP

Answer 7

CHORIONIC OR
GESTATIONAL SAC

Question 8

what’s the size of the yolk sac we start to worry about

Answer 8

over 6 mm

Question 9

when can you see babies heartbeat?

Answer 9

5+ LMP weeks

Question 10

TV can be seen on TV as early as

Answer 10

5 weeks

Question 11

A NORMAL GS GROWS ___
FROM __TO ___ WEEKS

Answer 11

A NORMAL GS GROWS 1.1MM/DAY
FROM 5 TO 8 WEEKS

Question 12

EMBRYO WILL BE SEEN AT

Answer 12

16 MM

Question 13

YS WILL BE PRESENT WHEN A MSD IS

Answer 13

8mm

Question 14

GS LARGER THAN — MM WITH OUT A YOLK SAC OR LARGER
THAN — MM WITHOUT AN EMBRYO

Answer 14

8mm, 16mm WATCH CAREFULLY FOR
IMPENDING EARLY PREGNANCY FAILURE

Question 15

yolk sac TA vs EV

Answer 15

TA = 20MM MSD
MEAN SAC DIAMETER (MSD)
EV = 8MM MSD

Question 16

UP TO WEEK 10

Answer 16

EMBRYONIC PERIOD

Question 17

WEEK 11 -

Answer 17

THE EMBRYO IS NOW CALLED A “FETUS”

Question 18

RL USED UNTIL ____ TO _____ WEEKS
_____________ = AGE IN WEEKS

Answer 18

12-13
CRL IN CM + 6 = AGE IN WEEKS

Question 19

umbilical cord FORMED AT WEEKS

Answer 19

6

Question 20

By 6 weeks EMBRYO SHOULD BE SEEN BY

Answer 20

TV 25mm

EV 16mm

Question 21

5 weeks CRL =

Answer 21

2-4mm

Question 22

MSD _________ = days of pregnancy

Answer 22

MSD (in mm) + 30 = days of pregnancy

Question 23

Best CRL is between

Answer 23

45-84mm

Question 24

8 weeks

Length = length

Answer 24

Head length = torso length

Question 25

At ___ weeks 3 brain vesicles develop

Answer 25

1) PROSENCEPHALON "FOREBRAIN". - TELENCEPHALON - ANT BRAIN & LATERAL VENTRICLES - DIENCEPHALON - POST BRAIN & 3RD VENTRICLE 2) MESENCEPHALON " MIDBRAIN" 3) Hindbrain (rhombencephalon)

Question 26

____ WEEKS The crescent-shaped sonolucency in the anterior aspect of the brain is created by the diencephalon and mesencephalon.

Answer 26

9 WEEKS The crescent-shaped sonolucency in the anterior aspect of the brain is created by the diencephalon and mesencephalon.

Question 27

Skull contains lateral ventricles

Answer 27

12 weeks

Question 28

Heart rates 5-6 weeks 6+ weeks

Answer 28

100 bpm 120-160bpm

Question 29

Alarm principle used in 1st trimester Vs 2-3rd trimester

Answer 29

THERMAL INDEX (TI) • TIS (THERMAL INDEX FOR SOFT TISSUE) USED IN FIRST TRIMESTER OB IMAGING • TIB (THERMAL INDEX FOR STRUCTURES NEAR BONE USED IN SECOND/THIRD TRIMESTER OB IMAGING

Question 30

•AMNIOTIC & CHORION - NORMALLY FUSE AT—- WEEKS

Answer 30

16

Question 31

Midgut herniation bowel usually how many mm at how many weeks What week do we stop seeing

Answer 31

6mm 7-10 weeks Not seen after 12 weeks

Question 32

Implantation bleed seen at how many weeks? ? Days from lmp

Answer 32

6-10 weeks 21 days since lmp