Induction of labour

Question 1

What is the definition of ‘induction of labour’?

Answer 1

the initiation oflabourby artificialmeansprior to its spontaneous onset at a viable gestational age, with the aim of achieving vaginal delivery in a pregnant woman with intact membranes

Question 2

What are some obstetric indications for induction of labour?

Answer 2

Uteroplacental insufficiency

Prolonged pregnancy

Intrauterine growth retardation

Prelabour rupture of membranes

Antepartum haemorrhage

Poor obstetric history
Intrauterine death

Maternal request (exceptional circumstances)

Question 3

What are some medical indications for induction of labour?

Answer 3

Severe HTN

Uncontrolled DM

Renal disease

Malignancies (facilitate definitive therapy)

Question 4

When does NICE say induction go labour should be done?

Answer 4

Benefit > risk

The process of induction of labour should only be considered when vaginal delivery is felt to be the appropriate route of delivery

Question 5

Why is IoL important in prolonged pregnancy?

Answer 5

Pregnancy extends past the due date there is increase in perinatal mortality as a result of decreased placental function

Question 6

Why are pre-labour rupture of membranes a concern?

Answer 6

Risk of infection to baby - contact with outside world

Question 7

What are some ABSOLUTE contra-indications for IoL?

Answer 7

Acute fetal compromise
Unstable lie
Placenta praevia
Pelvic obstruction

Question 8

What are some relative contraindications for IoL?

Answer 8

Previous cs
Breech
Prematurity
High Parity

Question 9

What things do people often believe are useful for IoL BUT ARE NOT supported by evidence?

Answer 9

herbal supplements
acupuncture
homeopathy
castor oil
hot baths
enemas
sexual intercourse

Question 10

What is membrane sweeping? When is it done?

Answer 10

Type of vaginal examination - aka stretch and sweep

Artificial membrane separation

Done before induction to try and prevent the need for full induction (hope this will start labour by releasing prostaglandins)

Question 11

How is a membrane sweep done?

Answer 11

Finger into cervical os which digitally separates the membranes of the cervix

May be done once, or additional sweeping may be offered

Question 12

When is a membrane sweep done in a nulliparous woman?

Answer 12

40-41 week antenatal visit

Question 13

When is a membrane sweep done in a multiparous woman?

Answer 13

41 week antenatal visit

Question 14

Other than brining on labour, what else might a membrane sweep result in?

Answer 14

‘more favourable’ cervix

Question 15

what percentage of women go in to spontaneous labour within 7 days of a membrane sweep?

Answer 15

30%

Question 16

What scoring system is used to assess for favourability of IoL?

Answer 16

Modified Bishop’s score

Question 17

What is the max score of Bishop’s score?

Answer 17

10

Question 18

What Bishop’s score indicates a favourable cervix?

Answer 18

> 8

Question 19

How is the position of the cervix scored in Bishop’s score?

Answer 19

Posterior: 0

Axial: 1

Anterior: 2

Question 20

What is the preferred method of IoL?

Answer 20

Vaginal prostaglandins (PGE2)

Question 21

What are the two main effects of PGE2?

Answer 21

Cervix: promotes ripening

Uterus: smooth muscle contraction

Question 22

How is PGE2 given to patients? What delivery methods exist?

Answer 22

Given PV

Inserted into posterior fornix

Gel, tablet, suppository, pessary

Question 23

Other than PGE2, what can be given to induce labour?

Answer 23

Oxytocin infusion (syntocinon)

Start low dose, titrate up

Question 24

Why wouldn’t you give oxytocin infusion to a woman with a low bishop’s score?

Answer 24

Cervix wouldn’t be ready

oxytocin doesn’t have any impact on cervix

Question 25

How does the length of cervix (degree of effacement) score on Modified Bishop’s score?

Answer 25

2cm = 0

1 cm = 1

<0.5cm = 2

Question 26

Which symptoms post early rupture of membranes would make you worry about infection?

Answer 26

Vaginal discharge

Abdo pain

Question 27

How does dilation of cervix score in Modified Bishop’s score?

Answer 27

0 cm = 0

1 cm = 1

> =2cm = 2

Question 28

How does station of presenting part score on Modified Bishop’s score?

Answer 28

• 2 = 0
• 1 = 1

0 = 2

Question 29

What would you need to assess prior to commencing IoL?

Answer 29

Favourability of cervix 
Obstetric examination (lie, cephalic presentation and engagement) - CALCULATE MODIFIED BISHOP'S SCORE

MEWS score

CTG

Question 30

What is oxytocin?

Answer 30

Hormone released by posterior pituitary which causes smooth muscle of uterus to contract

Question 31

When is oxytocin used?

Answer 31

Can be used to induce labour

MORE COMMONLY TO AUGMENT LABOUR

Question 32

Other than to augment labour, when might oxytocin be given?

Answer 32

When membranes have ruptured (either naturally or artificially)

Question 33

What do you need to monitor when giving a patient an IV oxytocin infusion?

Answer 33

CTG

Question 34

What do you need to monitor when giving a patient an IV oxytocin infusion?

Answer 34

CTG (baby’s heart rate)

Question 35

What can be done to cause membrane rupture in a lady who is undergoing IoL?

Answer 35

Artificial rupture of membranes (ARM)

aka: amniotomy

Question 36

How is ARM/amniotomy done?

Answer 36

Ruptured tool - amnihook

Question 37

What are the complications of IoL?

Answer 37

Foetal distress
precipitate delivery
instrumental/operative delivery  
uterine hypertonia with possible rupture
amniotic fluid embolism
systemic effects

Question 38

Do you have to have consent for IoL?

Answer 38

Yes - need to explain reasons for induction and possible consequences of accepting/declining the procedure