Normal Labour Flashcards
Define normal labour?
Spontaneous labour at term (37-42 weeks) with fetus in vertex position resulting in a Spontaneous Vaginal Birth (SVD)
What physiological changes must occur for labour to initiate?
- Cervix softens
- Myometrial tone changes to allow for coordinated contractions
- Progesterone decrease whilst Oxytocin and Prostaglandins increase
How many stages of labour are there?
3
What are the parts of Stage 1 of labour?
Latent first stage
Established first stage
What occurs during the latent first stage of labour?
Intermittent painful contractions leading to up to 4cm of dilatation
What occurs during the Established first stage of labour?
Regular Painful contraction producing progressive cervical effacement and 10cm dilatation
How long does the first stage last?
Established first stage lasts an average 8 hours primagravida and 5 multigravida
Progresses at 0.5-1cm per hour
What occurs during stage 2 of labour?
Phase from full cervical dilation to birth of baby
What occurs in the Passive 2nd stage of labour?
This is the stage after your fully dilated but before Involuntary Expulsive Contractions occur
Allow 1 hour for the fetus to descend
What occurs in the Active Second stage of Labour?
Expulsive contractions with full dilatation
The presenting part of fetus is visible and active maternal effort is required
How long does the Active phase of Stage 2 of labour take (difference between primagravida and multigravida)?
Average 2 hrs of Stage 2 starting for primagravida and 1hr for multigravida
What occurs during the 3rd stage of labour?
Expulsion of the placenta and membranes
What are the different ways we can handle the 3rd stage of labour?
- Active Management
* Physiological management
Describe the active and physiological management options for stage 3
- Uterotonic drugs
- Deferrend clamping and cutting of cord
- Controlled cord traction
Physiological means no drugs, don’t clamp till it stops pulsating and deliver placenta by maternal effort alone
When is prolonged third stage diagnosed?
After 30 minutes of birth with active management or within 60 minutes of birth with physiological management
We use a partogram once established labour has been confirmed to monitor the labours progress.
What tests/measurments would this include?
- Abdominal Palpation
- Vaginal Exam
- Monitoring colour, smell and volume of liquor
- Fetal Heart rate
- Palpate Uterine muscle contractions
- External signs
- BP/Pulse/Temp/RR/O2Sat/Urine output/Urinalysis
What does abdominal palpation tell us about the labour?
Fetal Lie Presentation Attitude Denominator Position Engagement
Define Fetal Lie
Axis of foetus to mother. Either Longitudinal (same axis as mum) or transverse (lying sideways) or Oblique
Define Fetal Presentation
The part of the foetus that is foremost in the birth canal
Define Fetal Attitude
Foetus’s posture - way body is flexed
i.e. back concave, straight or convex and head tilted forward or back
Define Fetal Position
Orientation of the foetus. Determined by which way the occiput (post fontanelle is facing)
1) Anterior vs posterior vs transverse
2) and left vs right
Define foetal Engagement
Degree to which the baby’s presenting part (head in vertex) has entered the pelvic inlet
What can be found on vaginal exam?
Foetal presentation, engagement and position
Cervical effacement and dilatation
Presence/absence of membranes
How do we auscultate the foetal heart?
Intermittently with Hand held doppler or pinard
OR Continuously with Cardiotocograph (CTG)
How often should be auscultate the foetal heart if doing it intermittently?
Every 15 minutes in first stage and 5 minutes in 2nd stage
How often/long do you hope for when palpating uterine muscle contractions?
3-4 every 10mins lasting 40-60s each
And moderate to strong not weak
What are some external signs of labour?
Rhomboid of Michaelis
Anal Cleft line
What are the parts to the mechanism of labour?
- Descent
- Flexion (of head)
- Internal rotation of head (so facing downward)
- Crowning and extension of head
- Shoulders rotate internally
- Head gets out and rotates to face sideways (restitution)
- External rotation of head
- Lateral flexion to deliver shoulders (Ant first then Post)
What forms of analgesia can women get during labour?
- Entonox
- Opioids
- Epidural
- Breathing and massage
- TENS
- Paracetamol and Dihydrocodeine
- Remifentanil Patient controlled Analgesia
- Water
What is entonox?
Inhalation Nitrous Oxide and oxygen
Aka gas and air
Why does progesterone decrease during labour?
As it inhibits uterine contractions
What is oxytocin and what is its action during labour?
A peptide hormone which releases prostaglandins from the uterine wall which causes uterine muscle contraction
What changes occur to the cervix during stage 1 of labour?
Moves forward, thins, softens and dilates
What are the two phases in stage 2 of labour?
Passive and active
What does it mean by a Primagravida birth and a multigravida birth?
Primigravida - woman who is pregnant for the first time
Multigravida - woman who has been pregnant more than one time
What is the normal position of foetus during expulsion?
Longitudinal lie, attitude is one of good flexion, presentation is cephalic, position is LOA or ROA, denominator is the occiput, the presenting part is the anterior parietal bone
