Labour

Question 1

What are the cardinal movements of labour?

Answer 1

1. Descent (Engagement)
2. Flexion
3. Internal rotation
4. Extension
5. External Rotation
6. Expulsion

Question 2

What are the stages of labour?

Answer 2

1. Onset of labour to complete dilatation (0-10cm)

• Latent Phase
  
  • infrequent/irregular uterine contractions
  • slow cervical dilation (usually to 4cm)
• Active Phase
  
  • rapid cervical change to complete dilatation
  • painful, regular contractions

2. Complete cervical dilation to neonate delivery

• pushing starts
• Cardinal movements occur
• duration of this stage depends on parity, contraction quality, + type of analgesia

3. Delivery of the placenta

• if >30min intervention is indicated
• demonstrated by gush of fresh blood, umbilical cord lengthening, uterine fundus changing shape
• active management: IV oxytocin to reduce risk of PPH (by >40%)

4. First postpartum hour

• monitor vital signs + bleeding, repair lacerations
• ensure uterus is contracted
• inspect placenta for completeness + umbilical cord for 2 arteries 1 vein
• 3rd + 4th stages most dangerous for mum

Question 3

What is failed induction of labour?

Answer 3

Failure to have regular (every 3 minutes) contractions and failure of the cervix to change after at least 24 hours of oxytocin (and if the water has been broken, if possible)

Question 4

What is active labour?

Answer 4

When the cervix is between 3-4 cm dilated; this is when you should see the beginning of a rapid increase in cervical dilation

▪ Women may not reach active labour until 6 cm dilation

▪ Experienced moms will have a faster speeding-up of labour at this point than first-time moms

Question 5

What is arrest of the first stage?

Answer 5

Diagnosed when a woman is in active labour (3-4 cm) and she has contractions with no change in dilation for more than 2 hours

1st stage arrest can be diagnosed ONLY if:

• Woman has reached 6 cm and the water has broken
• AND there has been no cervical change for:
  
  • 4 or more hours of adequate contractions
  • OR; 6 or more hours of inadequate contractions

If the mum is still <6 cm, then she needs additional time and interventions before an arrest of labour can be diagnosed, because she is still in early labour

Question 6

What are the 2 ways to diagnose arrest in the 2nd stage

Answer 6

WHEN PUSHING TAKES PLACE:

• >3 hours in first-time moms with an epidural,
• >2 hours in first-time moms without an epidural,
• >2 hours in experienced moms with an epidural,
• > 1 hour in experienced moms without an epidural

NO IMPROVEMENT IN DESCENT OR ROTATION AFTER:

• ≥ 4 hours in first-time moms with an epidural,
• ≥ 3 hours in first-time moms without an epidural,
• ≥ 3 hours in experienced moms with an epidural,
• ≥ 2 hours in experienced moms without an epidural

Question 8

What are some ways of monitoring the fetus during labour?

Answer 8

• External
  
  • CTG
  • auscultation with doppler
  • vaginal examination
• Internal
  
  • fetal scalp electrode
  • fetal scalp blood sample
  • intrauterine pressure catheter (contraction monitor)

Question 9

When to diagnose failure to progress

Answer 9

The diagnosis of failure to progress is made when:

1. The woman is in active labour (6cm or more) and has failed to progress despite 4 hours of adequate uterine activity, or at least 6 hours of oxytocin with inadequate uterine activity and no cervical change. (with ruptured membranes) (ACOG 2014)
2. Second stage of labour: 2 hours of pushing in multiparous and 3 hours in nulliparous