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Flashcards in PREGNANCY Deck (43)
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1

what produces human chorionic gonadotropin (hCG) and when is it produced?

produced by trophoblasts when they begin endometrial invasion

2

what are the effects of hCG?

- maintenance of the corpus luteum
- stimulation of oestrogen and progesterone production
- this prevents menstruation

3

when does hCG production peak?

at 60 - 80 days after the last menstruation
it then rapidly decreases but maintains a low concentration until the end of pregnancy

4

what is the effect of hCG levels decreasing?

the placenta increases secretion of oestrogen and progesterone

5

which hormone is detected on pregnancy tests?

hCG

6

where is prolactin produced?

it comes from the anterior pituitary

7

when is prolactin produced?

levels increase at the end of pregnancy when oestrogen and progesterone decrease

8

what is the role of prolactin?

it is involved in milk production and prevention of ovulation
the release is controlled by suckling

9

where is relaxin produced and when is it released?

it is produced by the ovaries and placenta
the levels increase in early pregancy

10

what is the role of relaxin?

it limits uterine activity
softens the cervix
ripens the cervix

11

when and where is oxytocin produced?

it comes from the posterior pituitary
it is secreted throughout pregnancy but levels increase towards the end of pregnancy

12

what is the role of oxytocin?

it stimulates uterine contractions
it triggers caring behaviours

13

what are the 2 different types of prostaglandin involved in pregnancy?

PGF2a = most abundant
PGE2 = 10 x stronger

14

where is prostaglandin produced and what is it's role?

produced by uterine tissue
it initiates labour

15

where is oestrogen and progesterone produced?

by corpus luteum
it regresses after 3 months and the placenta continues to produce oestrogen and progesterone

16

how does the placenta produce oestrogen and progesterone?

- placenta has enzyme capable of producing progesterone
- placenta contains aromatase which converts androgens to oestrogen

17

where do androgens for oestrogen come from?

- maternal ovaries
- maternal adrenal medulla
- foetal adrenal medulla

18

how are ovarian cycles inhibited during pregnancy?

GnRH is inhibited by increased progesterone
this means that there is low LH and FSH
therefore there is no ovarian cycle

19

what are the different types of maternal adaptations that occur in pregnancy?

cardiovascular changes
respiratory changes
GI changes
Skin changes
biochemical changes

20

what cardiovascular changes occur during pregnancy?

- increased cardiac output
- decreased systemic BP
- decreased total peripheral resistance (TPR)
- increased uterine blood flow
- increased blood volume
- increased plasma and blood cell mass

21

what respiratory changes occur during pregnancy?

increased alveolar ventilation
displacement of the diaphragm
increased risk of apnea and dyspnea
hyperventilation

22

what GI changes occur during pregnancy?

- increased acid reflux
- delayed gastric emptying - gastroparesis
- these are both due to the foetus pressing on the stomach

23

what skin changes occur during pregnancy?

- linea nigra - dark line down the central abdomen
- striae gravidae - stretch marks on lower abdomen
- darkened areolar on breasts

24

what biochemical changes occur during pregnancy?

- weight gain
- increase protein and lipid synthesis
- insulin resistance

25

how long does pregnancy last for?

40 weeks from day of last menstrual cycle
38 weeks from ovulation/conception

26

how are contractions prevented in early pregnancy?

most smooth muscles of the myometrium are disconnected from each other
this is maintained by progesterone

27

what changes occur in the uterus to prepare for contractions in labour?

an increase in oestrogen towards the end if pregnancy signals smooth muscle cells to produce connexins to form gap junctions
this allows coordinated contractions

28

what is cervical ripening?

it is the growth and remodelling of the cervix
this is due to the breakdown of collagen fibres that seal the uterus

29

what stimulates cervical ripening?

an increase in oestrogen towards the end of pregnancy
also caused by progesterone and relaxin

30

what is parturition?

it is the birth process
it the the successful transition from intra-uterine to extra-uterine life
events occur in the uterus and foetus in the last few weeks that culminate in delivery