Normal Labour

Question 1

What is ‘normal labour’?

Answer 1

Is where foetus, placenta and membranes are expelled via birth canal and is:

• Spontaneous
• 37-42 weeks gestation
• Foetus presenting by the vertex
• Results in a spontaneous vaginal birth

Question 2

What weeks of gestation for birth is considered normal?

Answer 2

• 37-42 weeks gestation

Question 3

What initiates labour?

Answer 3

It is not known what initiates labour, but its caused by interplay between paracrine and autocrine signals from maternal, foetus and placenta

Question 4

What key physiological changes occur that allow expulsion of foetus?

Answer 4

• Cervix softens
• Myometrial tone changes to allow for coordinated contractions
• Progesterone decreases whilst oxytocin and prostaglandins increase to allow for labour to initiate

Question 5

What are the 3 stages of labour?

Answer 5

• First stage
  
  • Split into
    
    • Latent phase
      
      • Can be longest part of labour, irregular contractions, cervical changes and dilation up to 4cm
    • Active phase
      
      • Length varies from 8-12 hours, regular and painful contractions, cervix is 4-10cm
    • Transition
      
      • Cervix is 8-10cm, physical changes such as shaking, vomiting or need to empty bowels
• Second stage
  
  • From full dilation to birth of baby
  • Passive second stage of labour
    
    • Assessed woman is fully dilated, but no involuntary contractions
  • Active second stage of labour
    
    • Is expulsive contractions or maternal efforts have been encouraged
  • Length is from 2-3 hours depending on if woman is nulliparous or multiparous
• Third stage
  
  • From birth of baby to expulsion of placenta and membranes
  • Can be managed physiologically or actively
    
    • Physiologically being where expulsion is done by maternal effort, no cord clamping
    • Active uses medication and cord clamping
  • Timing is generally up to an hour

Question 6

What can the first stage of labour be split into?

Answer 6

• Latent phase
  
  • Can be longest part of labour, irregular contractions, cervical changes and dilation up to 4cm
• Active phase
  
  • Length varies from 8-12 hours, regular and painful contractions, cervix is 4-10cm
• Transition
  
  • Cervix is 8-10cm, physical changes such as shaking, vomiting or need to empty bowels

Question 7

When is the second stage of labour?

Answer 7

• From full dilation to birth of baby

Question 8

What are the 2 stages of the second stage of labour?

Answer 8

• Passive second stage of labour
  
  • Assessed woman is fully dilated, but no involuntary contractions
• Active second stage of labour
  
  • Is expulsive contractions or maternal efforts have been encouraged

Question 9

When is the third stage of labour?

Answer 9

• From birth of baby to expulsion of placenta and membranes

Question 10

What are the different forms of management for the third stage of labour?

Answer 10

• Can be managed physiologically or actively
  
  • Physiologically being where expulsion is done by maternal effort, no cord clamping
  • Active uses medication and cord clamping

Question 11

What is the timing for the first, second and third stages of labour?

Answer 11

1st - longest part of labours, can be excess of 12 hours

2nd - 2 to 3 hours

3rd - up to 1 hour

Question 12

Describe the steps in the mechanism of labour?

Answer 12

1. Engagement and descent
2. Flexion
3. Internal rotation of the head
4. Crowning and extension of the head
5. Restitution
6. Internal rotation of head and external rotation of head
7. Lateral flexion of shoulders

Question 13

What are the different foetal lies?

Answer 13

Cephalic

Breech

Transverse

Question 14

What are the different foetal presentations?

Answer 14

Face

Brow

Vertex

Breech

Shoulder

Question 15

What are the different foetal positions?

Answer 15

Question 16

What is the normal foetal heart rate?

Answer 16

Normal foetal heartrate is 110-160bpm, with good variability (>5bpm) and accelerations (15bpm)

Question 17

How is the woman monitored during labour?

Answer 17

• Maternal observations
• Abdominal palpation
• Vaginal examination
• Monitoring of liquor
• Palpation of contractions
• External signs such as Rhomboid of Michealis and anal cleft line

Question 18

How is the baby monitored during labour?

Answer 18

Depending on woman’s risk assessment monitoring of foetus’ heart is through intermittent auscultation or continuous monitoring:

• Intermittent auscultation with pinards stethoscope or a handheld Doppler
• Continuous monitoring done with cardiotocograph

Question 19

What are different forms of pharmacological and non-pharmacological support during labour?

Answer 19

• Maternal position and mobility
• Breathing and hypnobirthing techniques
• Massage
• Aromatherapy
• TENS
• Oral analgesia
• Water
• Entonox
• Opiods
• Remifentacil
• Epidural

Question 20

What are some pain relief options in labour?

Answer 20

• Non-pharmacological
  
  • Birthing ball
  • Birthing pool
  • TENS machine
  • Hyponobirth
  • Aromatherapy
• Simple drug therapies
  
  • Entonox
    
    • Administration – inhale
    • Advantages – safe, widely used, you control the breathing, quick acting, wears off in minutes
    • Side effects – dizziness, dry mouth, nausea
  • Diamorphine
    
    • Administration – IM
    • Duration – works within 30 minutes and lasts 4 hours
    • Side effects – nausea, sleepy, slow breathing
• Advanced techniques
  
  • Remifentanil PCA
    
    • Strong morphine like pain medication that is short acting
    • Administration – IV
    • Duration – takes 1 minute to have effect
    • Advantages – control it yourself by pushing button
    • Side effects – slow breathing. Drowsy, nausea, itchiness
  • Epidural
    
    • Duration – 20 minutes to start working
    • Advantages – button gives extra medicine which you control
    • Side effects – slow down pushing phase, risk of forceps, hypotension, itching, fever, headache

Question 21

For entonox:

• administration
• advantages
• side effects

Answer 21

• Administration – inhale
• Advantages – safe, widely used, you control the breathing, quick acting, wears off in minutes
• Side effects – dizziness, dry mouth, nausea

Question 22

For diamorphine:

• administration
• duration
• side effects

Answer 22

• Administration – IM
• Duration – works within 30 minutes and lasts 4 hours
• Side effects – nausea, sleepy, slow breathing

Question 23

What is remifentanil PCA?

Question 24

For remifentanil PCA:

• administration
• duration
• advantages
• side effects

Answer 24

• Administration – IV
• Duration – takes 1 minute to have effect
• Advantages – control it yourself by pushing button
• Side effects – slow breathing. Drowsy, nausea, itchiness

Question 25

For epidural: - duration - advantages - side effects

Answer 25

* Duration – 20 minutes to start working * Advantages – button gives extra medicine which you control * Side effects – slow down pushing phase, risk of forceps, hypotension, itching, fever, headache