Brainscape's Knowledge GenomeTM

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


See full index

Reproduction, Development and Ageing > Physiology of Pregnancy > Flashcards

Physiology of Pregnancy Flashcards

1
Q

How is hormone production different in humans vs animals?

A
  • Placenta not responsible for steroid production in other species
  • Humans produce greater quantity of hormones
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
2
Q

hCG shares an alpha chain with which hormones?

A

TSH, LH and FSH

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

Which structural difference gives hCG a longer half life than LH?

A

Extended B chain

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

hCG is produced exclusively by ____ and ____

A

Syncytiotrophoblast of the placenta and trophodecterm of the preimplantation blastocyst

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

When do hCG levels peak in pregnancy?

A

~10 weeks gestation

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

hCG levels peak at ___units/mL then drop to about ___units after 10 weeks

A

100,000

20,000

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
7
Q

What is the main function of hCG?

A

Luteal support

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

Oestrogen and progesterone prevent ____ and maintain the endometrium in a _____ form (in pregnancy)

A

Menstruation

Decidualised form

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

What kinds of tumours would cause an increased hCG?

A

Trophoblastic tumours - choriocarcinoma and hydatidiform mole

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

What is the role of hCG in male fetus pregnancies?

A
  • Stimulates Leydig cells

- Allows production of testosterone before pituitary has developed (no LH)

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

How can women with choriocarcinoma or hydatidiform mole become hyperthyroid?

A
  • Produce hCG

- Bind to TSH receptor or LH receptor in thyroid

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
12
Q

What is the biggest risk associated with tubal pregnancy?

A

Invasion of ovarian artery by extravillous trophoblasts -> exanguination

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

Oestrogens are produced by the ____

A

Feto-placental unit

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

What four things are necessary for oestrogen production?

A
  • Live fetus
  • Functioning fetal adrenals
  • Intact feto-placental circulation
  • Functioning placenta
How well did you know this?
1
Not at all
2
3
4
5
Perfectly
15
Q

The placenta does not express ____ and cannot produce oestrogen de novo

A

17a hydroxylase

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

Placenta produces ___ and ____

A

Oestrone and oestradiol

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
17
Q

Anencephalic pregnancies usually have low levels of ____

A

Oestrogens

How well did you know this?
1
Not at all
2
3
4
5
Perfectly
18
Q

Pregnancies complicated by preeclampsia are characterised by higher/lower than “normal” peripheral resistance

A

Higher

19
Q

What are the two cardiovascular adaptations in pregnancy?

A
  • Increased CO

- Reduced PVR

20
Q

The placenta produces ____ which is shunted to the ___ circulation and converted to ____ in the adrenals which are then taken back to the placenta where they are converted to ____

A

Progesterone
Fetal circulation
Androgens
Oestrogen

21
Q

How does oestrogen influence the cardiovascular adaptations of pregnancy?

A
  • Reduces vascular resistance
  • Alters ratio of type I:type III collagen in vessel wall
  • High levels not reached until 9 weeks (fetal adrenals induce synthesis)
22
Q

How does progesterone influence the cardiovascular adaptations of pregnancy?

A
  • SM relaxant
  • Effect primarily in the uterus
  • Effect not till ~10 weeks
23
Q

How does angotensin influence the cardiovascular adaptations of pregnancy?

A
  • Vasoconstrictor
  • Uteroplacentalunit produces large amounts of RAS
  • Effects of AII blunted in normal pregnancy
24
Q

How does NO influence the cardiovascular adaptations of pregnancy?

A
  • Produced by endothelial cells in response to shear stress of blood
  • Short half life, causes arterial wall relaxation and dilation
  • NO synthetase activity in some tissues is inc. in pregnancy
25
Q

Do haematological changes drive cardiovascular changes in pregnancy?

A
  • No

- Haematological changes are gradual and occur later

26
Q

In pregnancy, blood volume increases/decreases and haematocrit increases/decreases

A
  • Blood volume increases

- Haematocrit declines

27
Q

In pregnancy plasma volume increases by ___mL by ___ weeks and thereafter remains stable

A

1250mL

30 weeks

28
Q

How does the body account for hypervolaemia post partum?

A
  • Decline of blood volume by diuresis

- Slow loss of red cells with time postpartum

29
Q

What is the approx. blood loss in a singleton delivery?

A

500mL

30
Q

How do sperm affect the maternal immune system?

A
  • Seminal plasma immune suppressive

- Reduces effectiveness of components of immune system in vivo

31
Q

How does sperm exposure related to pre-eclampsia?

A
  • Repeated exposure beneficial in preventing

- Changing partners resets susceptibility

32
Q

Which infections are more severe in pregnancy?

A
  • Incidence of listerosis increased

- Leprosy more severe later in pregnancy

33
Q

What is the role of neutrophils in pregnancy?

A
  • Expansion in luteal phase of cycle
  • Peaks at 30 weeks and rises again in time for labour
  • May be importnat in cervical ripening
34
Q

What is the lymphocyte composition of the decidua?

A
  • Almost no B cells
  • 10% T cells
  • 70% specialised uterine natural killer-like T cells
35
Q

uNK cells lack the ____ receptor

A

CD16

36
Q

What is the distinction between spontaneous and recurrent miscarriage?

A
  • Spontaneous miscarriage - usually caused by genetic abnormalities in the embryo that are not compatible with life (25% pregnancies)
  • Recurrent miscarriage - when a woman has 3 or more miscarriages with the same partner
37
Q

What is the postulated role of T cells in recurrent miscarriage?

A

In pathological pregnancies there might be a maternal immune response to the foetus

38
Q

What is the mechanism of uterine growth in pregnancy?

A

Stretching of existing cells (vs proliferation of cells)

39
Q

How do the dimensions of the uterus change in pregnancy?

  • Mass
  • Volume
  • Length
A

70g -> 1100g
10mL -> 5L capacity (up to 20L)
- 50um -> 400-600um

40
Q

How does the composition of the cervix change in pregnancy?

A
  • Softens
  • Glands proliferate to occupy approximately 1/2 of cervical mass
  • Mucus plug
  • Decrease in collagen
  • Elastin unchanged
  • GAGs and water increase
41
Q

When is the growth trajectory of the fetus the greatest?

A

In the 2nd and 3rd trimesters

42
Q

How does uterine blood flow change?

  • 10 weeks
  • 28 weeks
  • term
A
  • 10 weeks = 50mls/min
  • 28 weeks 185 mls/min
  • term 500-700 mls/min
43
Q

What changes occur in the abdominal wall and skin in pregnancy?

A
  • Increased blood flow to skin
  • Pigmentation changes
  • Striae gavidarum (stretch marks)
  • Hair loss reduced
44
Q

What are the pigmentation changes that may occur in pregnancy?

A
  • Darkened nipples and areola
  • Linea nigra
  • Cholasma in neck and face

Reproduction, Development and Ageing (26 decks)

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