Normal Labour Flashcards
What is normal labour?
Labour is the process in which the foetus, placenta and membranes are expelled via the birth canal.
Normal labour is spontaneous in its occurrence at 37-42 weeks gestation. The foetus presents by the vertex and results in spontaneous vaginal birth.
What causes the initiation of labour?
Not fully understood.
Triggered by paracrine and autocrine signals generated by maternal, foetal and placental factors which interplay.
Key physiological changes must occur to allow for expulsion of foetus:
-Cervix softens
-Myometrial tone changes to allow coordinated contractions
- Progesterone decreases whilst oxytocin and prostaglandins increase.
What is stage 1 of Labour?
Begins with irregular contractions that aren’t too painful just uncomfortable.
Becomes established when contractions are regular, painful and every 3-4 minutes. Usually around 3-5cmm dilated. Midwives count from established stage.
Stage 1 is complete when cervix is fully dilated at 10cm.
Anticipated progress 0.5-1cm per hour.
What is the direction of contractions?
Start at the fundus of the uterus and move down and across. This exerts pressure on the foetal pole which encourages flexion and a well applied presenting part which in turn puts pressure on cervix to thin and dilate.
What is stage 2 of labour?
From full cervical dilation to the birth of the baby. Has a passive and an active stage.
What is the passive second stage of labour?
The finding of full dilation of the cervix before or in the absence of involuntary expulsive contractions. 2hrs max.
What is the active second stage of labour?
Presenting part is visible and expulsive contractions are present. Active maternal effort may be needed if there is an absence of expulsive contractions in the beginning.
How long would you expect a Primagravida woman to spend in the active second stage?
2hrs max before birth.
How long would you expect a Multigravida woman to spend in the active second stage?
1hr max before birth.
Body remembers the process.
What is stage 3 of labour?
The time from the birth of the baby to the expulsion of the placenta and membranes. May require active management - routine use of uterotonic drugs, optimal cord clamping, controlled cord traction or may have physiological management - no routine use of uterotonic drugs, no cord clamping until pulsation has stopped and delivery of the placenta by maternal effort.
When is the third stage of labour considered prolonged?
If it is not completed within 30mins of birth with active management or within 60mins of birth with physiological management.
How is mum’s progress and health monitored?
Maternal observations
Abdominal palpation
Vaginal examination
Monitoring of liquor - waters should be clear or pale straw colour. Signs of fresh blood or green indications complications.
Auscultation of the foetal heart.
Palpation of uterine muscle contractions.
External signs e.g rhomboid of Michaelis (when coccyx moves as baby comes into pelvis you see a diamond shape above buttocks).
How is the position of baby determined/
In relation to the occiput (posterior fontanelle).
We want babies to be in Left Occipito- anterior or Right Occipito- anterior position.
What is the basic mechanism of labour?
Descent Flexion Internal rotation of the head Crowning and extension of the neck. Restitution Internal rotation of the shoulders. External rotation of head. Lateral flexion.
What are some forms of analgesia used in pregnancy?
Breathing Massage TENs Paracetamol Dihydrocodeine Water Entonox Opioids (morphine, diamorphine, pethidine). Remifentanil patient controlled analgesia. Epidural Maternal position
