Normal Labour and Delivery Flashcards
What is the definition of labour?
Normal physiologic process during which the foetus, membranes, umbilical cord and placenta are expelled from the uterus - most women experience without complications
What is the WHO definition of normal labour?
Spontaneous in onset, low risk at the start of labour and remaining so throughout labour and delivery, the infant being born spontaneously in the vertex position between 37-42 completed weeks of pregnancy
What is a low risk labour?
Labour in a woman without a pre-existing medical condition
What labours does ‘spontaneous’ (in the WHO definition of normal labour) rule out?
Induced labours
What is the normal labour time for prims?
12-18 hours
What is the normal labour time for multips?
6-8 hours
What might be mistaken for labour starting, but does not actually indicate the start of labour?
Braxton Hicks contractions - irregular, do not increase in frequency or intensity, “practice contractions”, don’t make any change to the cervix and are not sustained
Show - blood mucous plug from cervix, does not indicate start of labour, labour can occur weeks after this is expelled
PROM - pre-labour rupture of membranes, “waters broken”, can be a day or more before labour starts, or weeks if pre-term
Not all women will rupture membranes, some will deliver baby in the sac, some will rupture at the same time as giving birth
What are the physiological factors that cause the initiation of labour?
Largely unknown
When does labour occur?
When factors which inhibit contraction and maintain a closed cervix diminish and are succeeded by the actions of factors which do the opposite
What brings about contractions?
An increase in intracellular free calcium
What increase intracellular free calcium and therefore stimulate uterine contraction?
Prostaglandins and oxytocin
What are the places where labour commonly occurs?
Labour ward - high intervention, acute medical setting, generally women are monitored, IV access
Midwives unit - low risk, low intervention, analgesia, pool births possible, intermittent auscultation, encourage mobility
Home - midwife has to attend
BBA
What is the first stage of labour?
Begins with regular contractions and ends at full dilatation
What is the second stage of labour?
Starts with full cervical dilatation and ends with the delivery of the foetus
What is the third stage of labour?
Period between the delivery of the foetus and the delivery of the placenta and foetal membranes, can take 10 minutes-1 hour
What is needed in order to labour effectively?
At least 4 strong contractions, lasting at least 40 seconds, in 10 minutes
What are mild tone contractions?
Contractions lasting < 20 seconds
What are moderate tone contractions?
Contractions lasting < 40 seconds
What are you examining for when examining the station of the baby’s head?
Relation of baby’s head to ischial spine
Position of baby’s head - needs to be in the correct position for delivery
What are the phases of the first stage of labour?
Latent
Active
What is the latent phase of the first stage of labour?
Involves contractions which shorten the cervix and start dilatation
What is involved in the initial evaluation of a woman in the first stage of labour?
Due date When contractions started - frequency and pain Any bleeding Movement of baby Observations Foetal heart rate Urinalysis Cx Membranes Colour of liquor Meconium
What is the passing of meconium associated with?
Foetal distress and poor prognosis
What are the phases of the second stage of labour?
Passive
Active
What is the passive phase of the second stage of labour?
Where patient is fully dilated but waiting for powerful contractions to cause the baby to descend through pelvis and vagina, can carry on for as long as needed
What is the active phase of the second stage of labour?
Delivery by extension
Restitution and external rotation
Expulsion and delivery of shoulders
What prolongs the second stage of delivery and when is this not good?
Use of epidural anaesthesia
Not good in CV patients
What is involved in the third stage of labour?
The separation of the placenta, its descent to the lower segment and its expulsion with the membranes
Gush of blood, cord lengthening, rising fundus
Controlled cord clamping
(physiological or active)
