Normal labour Flashcards
What is the physiology of initiation of labour?
Progesterone decreases
Oxytocin and prostaglandins increase
Cervix softens
Myometrial tone changes allow for coordinated contractions
What is stage 1 labour?
Dilatation and effacement of cervix to 10cm
What are the stages of stage 1 labour?
Latent= intermittent irregular contractions allow for some effacement and dilatation up to 4cm Established= regular contractions --> progressive effacement and dilatation up to 10cm
What is the contraction ratio in established stage 1?
3-4/10 mins, lasting 40-60s
What is the duration of stage 1 labour in a prim?
Average 8
Max 18
What is the duration of stage 1 labour in parous?
Average 5
Max 12
What is failure to progress in labour?
Prim <0.5cm/hr
Parous <1cm/hr
What is stage 2 labour?
From full cervical dilatation until birth
What are the stages of stage 2 labour?
Passive= full cervical dilatation but no expulsive contractions Active= expulsive contractions with maternal effort and fully dilated cervix
What is the duration and purpose of passive stage 2?
~1 hour
Allow for further foetal descent
What is the duration of active stage 2?
Prim= 2 hours Parous= 1 hour
At what stage should forceps/Ventouse/section be considered?
After 1-2hours active labour
What is stage 3 of labour?
From birth of baby until expulsion of placenta and membranes
What are the ways to manage stage 3?
Active- if long/induced labour, ~30 mins
Physiological ~1 hour
What does active management of stage 3 involve?
Uterotonic drugs= syntometrine
Deferred clamping and cutting of cord
Controlled cord traction after separation of placenta
What is syntometrine?
Combination of syntocin and ergometrine
IM injection
Contraindicated in pre-eclampsia/hypertension
What is the physiological management of stage 3?
No clamping of cord until pulsation stopped
Delivery of placenta by maternal effort
Up to 60 mins
How often should foetal heart beat be monitored?
Stage 1= 15 mins
Stage 2= 5 mins
What are the indications for continuous CTG?
Suspected infection, temp >38 Hypertension >160/110 Oxytocin Significant meconium New vaginal bleed
What are the normal foetal positions during labour?
- Engagement of foetal head in transverse position
- Descent and flexion
- Internal rotation to occipital-anterior
- Delivery by extension
- Rotation to transverse for delivery of shoulders