Module 5- OB Intro

Question 1

Timelines of the trimesters

Answer 1

1st: 0 days-12w6d
2nd: 13 weeks- 27w6d
3rd: 28 weeks- 40 weeks

Question 2

What bloodwork happens and when?

Answer 2

1st: PAPPA and hCG
16 weeks: triple and quad screen
24-28 weeks: glucose tolerance screen

Question 3

When is it called and embryo and when is it called a fetus?

Answer 3

After 10 weeks the embryo becomes the fetus

Question 4

What is the purpose of the zona pellucida?

Answer 4

Prevents other sperm from getting into the egg

Question 5

What is the purpose of the corona radiata?

Answer 5

Provides nutrients to the ovum

Question 6

Where does fertilization occur in the female pelvis?

Answer 6

Ampullar portion of the Fallopian tubes

Question 7

When is implantation complete by?

Answer 7

11-12 days post ovulation/9-10 days post fertilization

Question 8

Syncytiotrophoblast produces what?

Answer 8

hCG

Question 9

Which is the more external one, which is more internal?:
-syncytiotrophoblast
-cytotrophoblast

Answer 9

Syncytiotrophoblast- external
Cytotrophoblast- internal

Question 10

What is the early placenta?

Answer 10

Chorion frondosum (which is part of the cytotrophoblast)

Question 11

Describe the decidua layers of the uterus (3)

Answer 11

1. Decidua basalis- underlying the conceptus and becomes the maternal side of the placenta
2. Decidua capsularis- covers over the gestational sac
3. Decidua parietalis(Vera)- all remaining decidua

Question 12

Describe the 3 layers of the trilaminar disc

Answer 12

1. Endoderm: inner (linings GI and respiratory tract)
2. Ectoderm: outer (forms CNS and surface of the ectoderm- hair, skin, teeth, nails)
3. Mesoderm: middle (forms muscle and bone)

Question 13

When is the yolk sac seen on ultrasound?

Answer 13

From 5 weeks to about 10-12 weeks

Question 14

What is the upper limit of normal for the yolk sac before 10 weeks?

Answer 14

6mm

Question 15

How much does the gestational sac grow per day?

Answer 15

1.1mm/day

Question 16

When should fetal heart motion be detected?

Answer 16

5mm or greater

Question 17

When do B hCG levels plateau?

Answer 17

8 weeks

Question 18

What do high B hCG levels indicate? Low levels?

Answer 18

High- twins, moles, choriocarcinoma, teratomas, gonadotropin producing tumours
Low- ectopic, fetal demise, inaccurate dates

Question 19

Pseudocyesis

Answer 19

A woman feels pregnant. But isn’t.

Question 20

Single set of unpaired chromosomes (23)

Answer 20

Haploid

Question 21

Paired chromosomes

Answer 21

Diploid (46 chromosomes- 23 pairs)

Question 22

3 complete chromosome sets (69 chromosomes)

Answer 22

Triploid

Question 23

Condition where there is one extra chromosome present in each cell additional to the normal diploid (46 becomes 47)

Answer 23

Trisomy

Question 24

Karyotype meaning

Answer 24

How chromosomes are expressed