Labour Flashcards Preview

Y2 LCRS RDA Fwong > Labour > Flashcards

Flashcards in Labour Deck (24)
Loading flashcards...
1
Q

How many weeks of gestation is defined as “term”?

A

37-41

2
Q

Recall the boundaries of “pre-term” and “very pre-term” delivery

A

22-37 weeks

very preterm- 22-28

3
Q

Recall the factors moderating the cervical changes that occur in labour

A

PGE2
IL8
MMPs

4
Q

Recall the factors moderating the endometrial changes that occur in labour

A

PGE2

Oxytocin receptor upregulation

5
Q

Where is PGE2 produced in labour?

A

Foetal membranes

6
Q

Describe the changes in the foetal membranes during labour?

A

Inflammatory process occur, and the FMs secrete PGs, ILs and MMPs

7
Q

Summarise the endocrine and biochemical promotors of labour

A

Promotors of labour requires pro-inflammatory factors.
Key regulators: CRH, PAF, Progesterone and NFKB. (CRH, PAF and NFKB are proinflammatory and pro-labour, progesterone is anti-labour)
CRH and PAF upregulate pro-inflammatory cytokines
NFKB is the key TERM labour initiator but is normally inhibited by progesterone. Progesterone loses its anti-labour effects at term and this allows NFKB to initiate labour

8
Q

Summarise how progesterone loses its anti-labour effects at term

A

Presence of progesterone/PR = proinflammatory genes will be switched off because the Progesterone-PR complex inhibits the transcription factor NFKB which normally transcribes these proinflammatory proteins.

During normal TERM labour:
functional progesterone withdrawal (slide 65) leads to increased NFKB activity= activation of proinflammatory genes= labour

9
Q

What is the role of NFKB in labour?

A

Involved in pro-inflammatory processes, upregulates proinflammatory genes including cytokines, MMPs, oxytocin receptors

10
Q

Describe the epithelial changes in the foetal membranes during labout

A

Amnion epithelium on BM loses strength

11
Q

What 2 processes are undergone by the cervix in labour?

A

Effacement and dilatation

12
Q

What is cervical effacement?

A

Cervix becoming softer, thinner and more flexible

13
Q

What must happen in order for cervical effacement to occur?

A

Excessive ECM remodelling

14
Q

Recall the key mediators in uterine contraction in labour

A

PGE2 from foetal membranes

Oxytocin receptor

15
Q

How long does the onset of uterine contraction last in labour?

A

About 8 hours

16
Q

When do foetal membranes usually rupture?

A

During onset of labour

17
Q

What is the 2nd stage of uterine contraction, and how long does it last?

A

Expulsive effort

About 30 mins

18
Q

Name the 3 stages of labour

A
  1. Cervical ripening and effacement and onset of myometrial contraction
  2. Delivery of infant
  3. Delivery of placenta
19
Q

How long should the 3rd stage of labour last?

A

30 minutes

20
Q

Summarise the non-haematological events of the 3rd stage of labour

A

Uterus contracts very powerfully to expel the placenta, causing a rupture between the uterus service and the placenta –> delivery

21
Q

What conditions are required in the spiral arteries in order to achieve successful haemostasis in placental delivery

A

High flow and low pressure

22
Q

How does the myometrium control haemostasis following placental delivery?

A

Contracts forecefully

23
Q

What is involution and what drives it?

A

The powerful myometrial contraction that causes haemostasis of spiral arteries
Driven by oxytocin (contractile hormone)

24
Q

Summarise the hypothesis for parturition

A

CRH increase
Foetal adrenal stimulated
Positive feedback in lacenta between CRH and cortisol
Cortisol drives IL, PG and PAF production = pro-labour factors