Normal Labour Flashcards
What is labour?
The process in which the fetus, placenta and membranes are expelled via the birth canal characterised by cervical changes and contractions
How many weeks is term?
37-42
How long should labour typically last?
12-18 hours for first time pregnancy (can be half for subsequent pregnancies), but can vary
What changes occur for the initatation of labour?
Cervix softens: Contractions pull on cervix causing it to thin and dilate, allowing fetus to leave
Myometrial tone changes to allow for coordinated contractions
Progesterone decreases whilst oxytocin and prostaglandins increase to allow labour to initiate
What is the latent first stage of labour?
period during which there are intermittent, often irregular, painful contractions which bring about some cervical effacement and dilatation up to 4cm
When is stage 1 of labour complete?
When cervix is fully dilated (10cm)
How long does stage 1 of labour last?
8 hours (unlikely to last longer than 18 hours) for a primagravida
For a multigravida this stage lasts on average 5 hours (unlikely to last over 12 hours)
How long should 3rd stage of labour last?
Within 30 minutes of the birth with active management or within 60 minutes of the birth with physiological management.
What is the established first stage of labour?
Regular, painful contractions that result in progressive effacement and cervical dilatation from 4cm
What is the passive second stage of labour?
The finding of full dilatation of the cervix before or in the absence of involuntary expulsive contractions. Plan to allow one hour of passive second stage to allow for further fetal descent.
What is the active second stage of labour?
Expulsive contractions with a finding of full dilatation of the cervix.
How long does passive second stage of labour last?
1 hour to allow fetal descent
How long does active second stage of labour last?
In a primagravida birth would be expected within two hours of active second stage commencing.
For a multigravida birth would be expected within one hour of active second stage commencing.
What is the 3rd stage of labour?
The third stage of labour is the time from the birth of the baby to the expulsion of the placenta and membranes.
What does active management of the 3rd stage of labour involve?
routine use of uterotonic drugs: Drugs that stimulate contraction of the myometrium (oxytocins or prostaglandins)
deferred clamping and cutting of the cord
controlled cord traction after signs of separation of the placenta: Pressure applied until placenta is delivered
What does physiological management of the 3rd stage of labour involve?
No routine use of uterotonic drugs
No clamping of the cord until pulsation has stopped
delivery of the placenta by maternal effort
Describe false labour
Contractions felt in the lower abdomen
The contractions are irregular and occur every 20 minutes
Progressive cervical changes are absent.
When does false labour occur?
Last 4 weeks of pregnancy
What are the two types of C section?
Lower segment caesarean section
Classic caesarean section, involving longitudinal incision in the upper segment of the uterus
What is a category 1 C section?
Immediate caesarean section, performed where there is evidence or clinical suspicion of acute foetal compromise
What is a contraindication for vaginal delivery after C section?
Previous uterine rupture
Classical C section scar
Give the requirements for instrumental delivery
Fully dilated cervix generally the second stage of labour must have been reached
OA position preferably OP delivery is possible with Keillands forceps and ventouse. The position of the head must be known as incorrect placement of forceps or ventouse could lead to maternal or fetal trauma and failure
Ruptured Membranes
Cephalic presentation
Engaged presenting part i.e. head at or below ischial spines the head must not be palpable abdominally
Pain relief
Sphincter (bladder) empty this will usually require catheterization
Describe the stages of analgesia during labour
Non pharmacological methods
Nitrous oxide (gas and air)
Simple analgesia, such as paracetamol
Opiate analgesia, such as IV diamorphine or oral coedine
Epidural analgesia
Pudendal nerve block
