Normal labour

Question 1

What do we class to be a term pregnancy

Answer 1

37-42 weeks

Question 2

How is labour initiated?

Answer 2

Large release of oestrogen which triggers the release of prostaglandins which mediate activity during labour and make body more susceptible to oxytocin

Question 3

What changes do the prostaglandins stimulate?

Answer 3

Myometrium stretches and muscle contractility increases. Gap junctions form in myometrium facilitating better contraction
Decrease in collage and increase in water to make cervix softer and ready to stretch

Question 4

What are the two main phases of labour

Answer 4

LATENT from beginning of labour up to 4cm dilation
- can be managed at home
ESTABLISHED Dilation of 4cm up to delivery
- Should come in for midwife care

Question 5

What are the three stages of established labour?

Answer 5

1. Onset to full cervical dilation (10cm)
2. Delivery of baby
3. Delivery of placenta

Question 6

What two changes does the cervix go through during labour?

Answer 6

Dilation (stretching to 10cm)

Effacement (flattening against baby’s head)

Question 7

What is the expected rate of dilation during stage 1 of established labour?

Answer 7

2cm every 4 hours

Question 8

As well as cervical dilation what else is monitored to track the progress of labour?

Answer 8

Midwives also monitor the descent of the baby’s head (known as its STATION)
Positive is below the ischial spines (e.g. +1, +2, +3) and negative is above (-1, -2, -3)

Question 9

What are the further two stages of stage 2 of established labour?

Answer 9

PASSIVE AND ACTIVE LABOUR
PASSIVE = woman is fully dilated but is not yet having an explosive or involuntary contractions / urges to push
ACTIVE = expulsive contractions occur and women get very strong urge to push

Question 10

How should active labour be managed?

Answer 10

Should be slow and controlled - woman shouldn’t necessarily be pushing the whole time - important to have breaks
This reduces risk of perineal trauma and also harm to baby (blood supply is reduced, there is hypoxia when the woman is pushing)

Question 11

When should stage 3 of labour occur?

Answer 11

The delivery of the placenta will occur around 10-15 minutes after the delivery. Should be managed passively some might need ACTIVE MANAGEMENT

Question 12

What will active management of the 3rd stage of labour involve?

Answer 12

Uretotonics e.g. SYNTOMETRINE to help the uterus contract back down and stop bleeding

Question 13

What are some options for pain management in labour?

Answer 13

PHARMACOLOGICAL
NO, PCM, Opiates (diamorphine), Epidural (best cover)

NON-PHARMACOLOGICAL
Massage, water bath, Relaxation and breathing, mobilisation, TENS

Question 14

Does epidural have any impact on mode of delivery?

Answer 14

Slightly increased chance of instrumental delivery due to the decreased urge to bear down

Question 15

Summarise and explain the mechanisms of labour and the descent through the birth canal

Answer 15

Descent and flexion
Internal rotation of head (to face occipito-anterior)
Crowning
Extension of neck and delivery of head
Restitution (head rotates back in line with body)
Delivery of the anterior shoulder
Delivery of the posterior shoulder

Question 16

What are some contra-indications to epidural?

Answer 16

Increased risk of bleeding - so this is anyone with a haemoglobinopathy or anyone with HELLP (low platelets)
Anyone with previous reaction to LA

Question 17

What are some effects / risks of epidural?

What effect does it have on labour?

Answer 17

Drop in BP due to activation of autonomic pathway
There is a risk of post-dural puncture headache, infection and haematoma

It DOES NOT prolong labour
It DOES NOT increase the risk of CS
NO EVIDENCE of chronic back pain in women who had had them
SLIGHTLY INCREASES RISK OF INSTRUMENTAL DELIVERY