Chapter 3- Second Week of Development

Question 1

% of pregnancies that are extrauterine implantations

Answer 1

~2%

Question 2

beta hCG levels in extrauterine pregnancies

Answer 2

lower than normal pregnancies

Question 3

Placenta privia

Answer 3

placenta partially or fully covers uterine os

Question 4

placenta previa implantation site

Answer 4

inferior segment of uterus near internal os

Question 5

placenta previa symptoms/risks

Answer 5

bleeding

premature separation of placenta in pregnancy or labor

Question 6

threatened abortion

Answer 6

bleeding during pregnancy that increases the chances for abortion

Question 7

Threatened abortions:
% of all pregnancies
% of TA pregnancies that end in abortion

Answer 7

25% of all pregnancies

50% of TA pregnancies end in miscarriage

Question 8

Embryonic disc characteristics

Answer 8

• bilaminar
• forms epiblast and hypoblast
• gives rise to all germ layers

Question 9

End of 2nd week structures formed

Answer 9

amniotic cavity, amnion, umbilical vesicle, connecting stalk, and chorionic sac

Question 10

Blastocyst implants ___ days after ovulation and ___ days after fertilization

Answer 10

6-10

Question 11

Maximal blastocyst invasion after ____ days

Answer 11

9-12

Question 12

Extraembryonic coelom splits into..

Answer 12

extraembryonic somatic mesoderm

extraembryonic splanchnic mesoderm

Question 13

Extraembryonic somatic mesoderm

Answer 13

lines trophoblast

covers amnion

Question 14

Extraembryonic splanchnic mesoderm

Answer 14

surrounds umbilical vesicle

Question 15

prechordal plate forms ____ around _____

Answer 15

the mouth

14 days post fertilization

Question 16

Most common blastocyst implantation site

Answer 16

superior body of uterus on posterior wall

Question 17

After 5 days post fertilization…

Answer 17

zona pellucida degrades

Question 18

After 6 days post fertilization…

Answer 18

blastocyst adheres to endometrial epithelium

Question 19

After 7 days post fertilization…

Answer 19

trophoblast splits into synctiotrophoblast and cytotrophoblast

Question 20

After 8 days post fertilization…

Answer 20

blastocyst begins embedding

Question 21

After 9 days post fertilization…

Answer 21

blood filled lacuane appear in synctiotrophoblast

Question 22

After 10 days post fertilization…

Answer 22

blastocyst sinks beneath endometrial epithelium

Question 23

After 10-11 days post fertilization…

Answer 23

lacunar networks form

Question 24

After 11-12 days post fertilization…

Answer 24

uteroplacental circulation is established

Question 25

After 12-13 days post fertilization…

Answer 25

Endometrial epithelium defect is repaired

Question 26

After 13-14 days post fertilization…

Answer 26

primary chronic villi develop