Brainscape's Knowledge GenomeTM

Browse over 1 million classes created by top students, professors, publishers, and experts.


See full index

Reproductive system > Implantation, Placentation & Hormone Changes in Pregnancy > Flashcards

Implantation, Placentation & Hormone Changes in Pregnancy Flashcards

1
Q

What is Implantation?

A

blastocyst attaches to uterine wall

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

What are the Requirements for implantation?

A

Fully Developed Blastocyst

  • 5th/6th day of development
  • hatched out from zona pellucida

Receptive Endometrium

  • thickened endometrium during proliferative phase
  • expression of embryo receptivity markers to communicate with blastocyst
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
3
Q

Describe the Blastocyst structure.

A

Embryoblast (inner cell mass)
-forms foetus

Trophoblast (outer cells)
-forms placenta

Blastocoel (fluid filled cavity)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
4
Q

What is the embryonic pole of the blastocyst?

A

pole where embryoblast (inner cell mass) is located

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
5
Q

What is the aembryonic pole of the blastocyst?

A

pole where trophoblasts are concentrated

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
6
Q

When and how does the blastocyst hatch from the zona pellucida?

A

Day 5:

  • enzymes dissolve zona pellucida at aembryonic pole
  • rhythmic contraction enable blastocyst to herniate and bulge out of the zona pellucida
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

Why is hatching essential for implantation?

A

because the zona coat prevents blastocyst from communicating with endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
8
Q

What are the Stages of Implantation?

A

3 stages:

APPOSITION
-close positioning of blastocyst to endometrium (decidua basalis)

ATTACHMENT
-trophoblast cells attach to endometrium

INVASION
-trophoblast cells multiply and invade into endometrium, implanting embryo in endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
9
Q

Describe the Days 7-8 of the Implantation Timeline.

A

Blastocyst attaches to surface of endometrial wall

Trophoblast cells assemble to form Syncytiotrophoblast in order to facilitate invasion of endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
10
Q

Describe days Days 9-11 of the implantation timeline.

A

Syncytiotrophoblast further invades endometrial wall

By day 11, blastocyst is almost completely buried in endometrium

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
11
Q

Describe day 12 of the implantation timeline.

A

Decidual Reaction

  • high progesterone levels enlarge and coat decidual cells in glycogen and lipid-rich fluid
  • fluid taken up by syncytiotrophoblast to sustain the blastocyst before placenta is formed
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

Describe day 14 of the implantation timeline.

A

Syncytiotrophoblast cells protrude out to form tree-like structures “Primary Villi” which are then formed all around the blastocyst

Decidual cells between primary villi clear out, leaving behind empty spaces called Lacunae

Maternal arteries and veins start to grow into the decidua basali and merge with Lacunae; arteries fill them with oxygenated blood and veins return deoxygenated blood to maternal circulation

Blood filled lacunae merge into one large one pool of blood connected to multiple arteries and veins known as the Junctional Zone (circulatory foundation for placenta formation)

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
13
Q

When is the umbilical cord formed?

A

5th week
-then connected to capillaries formed by the foetal mesoderm cells which then feed into the junctional zone and supplied by maternal circulation

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
14
Q

What is the foetal contribution to the placenta?

A

Chorionic Frondosum

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

What is the maternal contribution to the placenta?

A

Maternal Spiral Arteries

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
16
Q

What happens in 4th/5th months of pregnancy to placenta?

A

decidual septa forms, dividing the placenta into 15-20 regions known as Cotyledons

this provides efficiency maternal-foetal exchange of nutrients due to an increase in surface area

17
Q

Placenta takes up…

A
  • O2 and glucose
  • immunoglobulins
  • hormones
  • toxins (in some cases)
  • amino acids
  • vitamins
  • minerals
  • fats
18
Q

Waste products the placenta drops off from foetus are…

A 
CO2
Waste products (urea, ammonia, etc)
19
Q

Where is the placenta formed?

A

upper part of the uterus

20
Q

What is the umbilical cord made of?

A

2 arteries and 1 vein

21
Q

What is the Pre-eclampsia?

A

maternal spiral arteries are fibrous and narrow, limiting blood supply to the placenta (placental insufficiency)

22
Q

What is Eclampsia?

A

preeclampsia + seizures

23
Q

Describe the Response of placenta to pre-eclampsia.

A

1) Secretes pro-inflammatory proteins that make way into maternal circulation and cause endothelial cell dysfunction
2) Endothelial cell dysfunction affects other body systems causing:
- vasoconstriction> maternal hypertension
- vasoconstriction>glomerular damage from hypertension> proteinuria

24
Q

What are the Risk factors for pre-eclampsia?

A
  • first pregnancy
  • multiple gestation
  • increased maternal age (>35)
  • hypertension
  • diabetes
  • obesity
  • family history of pre-eclampsia
25
Q

What is a Hydatidiform mole?

A

overgrowth of placental cells on uterus

26
Q

What is Placental Abruption?

A

maternal spiral arteries supplying blood to placenta degenerate and rupture, causing haemorrhage and premature separation of all or part of the placenta from the endometrium

27
Q

What are the Symptoms of placental abruption?

A

vaginal bleeding

pain in back/abdomen

28
Q

What are the Maternal Complications of Placental Abruption?

A
  • Hypovolaemic shock
  • Sheehan Syndrome (perinatal pituitary necrosis)- hypopituitarism
  • renal failure
  • disseminated intravascular coagulation (DIC)
29
Q

What are the Foetal Complications of Placental Abruption?

A

Intrauterine hypoxia and asphyxia

Premature birth

30
Q

What is Placenta Previa?

A

placenta implants in lower uterus, either fully or partially covering the internal cervical os

31
Q

What are the Risk factors for placenta previa?

A
  • previous C section
  • previous uterine/endometrial surgery
  • uterine fibroids
  • previous placenta previa
  • smoking & recreational drug use
  • multiple gestation
  • increased maternal age
32
Q

What is the Risk of placenta previa?

A

increased risk of pre-term birth and foetal hypoxia

33
Q

Which cells secrete hCG?

A

trophoblast cells in corpus luteum after implantation

34
Q

What is the basis of urinary tests?

A

β-hCG

35
Q

Initial hCG production is by…

A

corpus luteum

36
Q

Around week 7, hCG production is by…

A

placenta

*also decrease in hCG due to degeneration of corpus luteum

37
Q

What are the Hormones the placenta synthesizes and releases into maternal circulation?

A

Oestrogens from foetal androgens from foetal cortex

Progesterone from maternal cholesterol

human Placental Lactogen (hPL), making mother more insulin resistant so glucose available for both mother and foetus

Reproductive system (12 decks)

Brainscape helps you reach your goals faster, through stronger study habits.
© 2024 Bold Learning Solutions. Terms and Conditions