Induction of Labour Flashcards
What is required for a pregnancy to continue?
- Cervix to remain closed and rigid
- Uterus to remain quiet/ not contracting
- Progesterone = prevents stimulation of oxytocin receptors in the uterus
What triggers labour?
- Hormones
- Ferguson’s Reflex
- Prostaglandins
How do hormones trigger labour?
- Release of oxytocin which stimulates contractions of uterus
- Decreased progesterone levels
How does the Ferguson’s reflex trigger labour?
- Pressure on the cervix from PP
- Surge of oxytocin
- Uterus contracts
How do prostaglandins trigger labour?
- Produced by the chorion and amnion
- Soften and ripen cervix by breaking bonds between cells
What is the difference between induction and augmentation?
Induction = the artificial initiation of labour Augmentation = progress of labour is enhanced
Give some possible reasons for the increased induction rates
- Increased BMI = increased GDM
- Increased mat age
- More co-mordbidities
- More RFM awareness
- Maternal request
Give some foetal reasons for induction of labour
- Large for dates/ IUGR
- Multiple pregnancy
- 3 x RFM
- Foetal death
What is not a foetal indication for IOL?
Macrosomia with no other issues
Give some maternal reasons for induction of labour
- OC
- Pre-eclampsia
- Post dates
- Diabetes
- Pre-labour rupture of membranes
- Maternal request
Give some other reasons for induction of labour
- IVF
- Placenta function
- Obstetric history (precipitate labour, previous IUD, infertility, prev. large baby)
What is the difference between a prolonged pregnancy and post-maturity?
Prolonged pregnancy = >40/40
Post-maturity = a particular clinical syndrome during a pathologically prolonged pregnancy (>42/40)
When should an induction ideally take place?
40+10 to 40+14
Why should an induction take place before 42/40?
Fewer perinatal deaths, CS and infant morbidities
What risks are associated with induction/augmentation?
- Hyperstimulation
- Failed induction
- Uterine rupture
- Increased need for CS
- PPH (NICE 2014)
What does hyperstimulation increase the risk of?
- Foetal hypoxia
- Uterine rupture
- PPH
What does fluid overload increase the risk of?
- Cardiac arrest
- Pulmonary oedema