Implantation Endocrinology of Pregnancy

Question 1

Bottom layer of endometrium

Answer 1

basalis layer (1/3 of full thickness) –> not shed during menses –> contains epithelial, stromal, and vascular progenitor cells for proliferation and neovascularization of endometrium during proliferative phase under estrogen regulation

Question 2

Top 2/3 of full thickness endometrium shed during menses

Answer 2

Functionalis layer

Question 3

Is there a change in endometrium thickness during the secretory phase?

Answer 3

No

Question 4

The key hormone during proliferative stage

Answer 4

estrogen

Question 5

What are the minimal endocrine nees for normal cycling of the endometrium?

Answer 5

estrogen priming then progesterone

Question 6

The period of endometrial maturation which permits the attachment of the embryo and the establishment of pregnancy.

Answer 6

endometrial receptivity

Question 7

What maintains the early pregnancy?

Answer 7

corpus luteum stimulated by fetal hcg to release estrogen and progesterone

Question 8

What is the window of implantation in the human?

Answer 8

days 20-24

Question 9

At what stage of embryo development implantation occurs?

Answer 9

blastocyst

Question 10

How can a “5” cell or “3” cell embryo exist?

Answer 10

asynchronous division

Question 11

how many days does it take before implantation occurs?

Answer 11

6-7

Question 12

Which phase of implantation? hatched blastocyst is positioned in apposition to the endometrial epithelial cells

Answer 12

apposition

Question 13

Which phase of implantation? the trophoblast cells adjacent to the inner cell mass adher to the apical surface of the endometrial epithelial cells

Answer 13

adhesion

Question 14

Which phase of implantation? the trophoblast cells insinuate themselves in between the endometrial epithelial cells

Answer 14

intrusion

Question 15

Which phase of implantation? the trophoblst cells and ultimately the whole embryo invade through the basement membrane and the endometrial stroma and reach and invade into the maternal vessels

Answer 15

invasion

Question 16

The embryo becomes fully embedeed in the endometrium by day ____ post ovulation

Answer 16

12-14

Question 17

Implantation usually occurrs at the mid ____ endometrial surface

Answer 17

posterior

Question 18

Enzymes involved in implantation

Answer 18

MMP-9 collagenase, urokinase type plasminogen activator

Question 19

During implantation and placentation there is invasion of the ______ and remodeling through secretion of ____

Answer 19

maternal stroma and blood vessels through secretion of ECM

Question 20

Is invasion of embryo comparative to invasive activity of a neoplasm?

Answer 20

No –> trophoblast invasion is regulated with specific factors in trigger and arrest of the process

Question 21

____ cells invade maternal spiral arteries of the endometrium and replace the endothelial cells

Answer 21

trophoblast

Question 22

direct contact of maternal blood with trophoblastic chorion

Answer 22

hemochorial placentation

Question 23

At the core of each chorionic villus, there are fetal capillaries adjacent to the trophoblast layer and coalesce to form ____

Answer 23

umbilical vessels

Question 24

Fusion of cytotrophoblasts results in formation of ____

Answer 24

syncytiotrophoblast layer

Question 25

On the inside of each villus is a ____

Answer 25

fetal capillary

Question 26

Trophoblastts are derived from the _____ of the blastocyst

Answer 26

trophectoderm

Question 27

Endocrine trophoblast functions

Answer 27

hcg and p4 (and E) secretion by syncytiotrophoblast + exchange of nutrients and gases between mother and fetus

Question 28

T/F cytotrophoblasts secrete hcg

Answer 28

F –> only syncitiotrophoblasts

Question 29

T/F extent of trophoblast invasion can cause pathological situation

Answer 29

T –> preeclampsia, intrauterine growth restrictionk, preterm birth, maternal mortality