Normal labour

Question 1

What is labour and when does it happen?

Answer 1

• fetus, placenta + membranes are expelled through the birth canal- Spontaneous Vaginal Delivery (SVD)
• 37-42 weeks

Question 2

What 3 physiological changes must occur to allow expulsion of the fetus?

Answer 2

• cervix softens
• myometrial tone changes- allows coordinated contractions
• oxytocin + prostaglandins dec. whilst progesterone inc. for labour initiation

Question 3

What is the 1st stage of labour?

Answer 3

• cervix dilates 0.5-1cm/hr
• latent stage- up to 4cm
• intermittent, irregular contractions
• established stage- up to 10cm
• painful, regular contractions
• completed when cervix is fully dilated and effaced

Question 4

What is the 2nd stage of labour?

Answer 4

• from complete dilation to birth of baby
• primagravida birth within 2 hrs
• multigravida birth within 1 hr
• passive stage
• full cervical dilatation
• without involuntary contractions
• active stage
• presenting part of fetus visible
• expulsive involuntary contractions

Question 5

What is the 3rd stage of labour?

Answer 5

• from birth of baby to delivery of placenta and membranes
• active management- give oxytocin
• up to 30 mins
• physiological management- natural
• up to 60 mins

Question 6

What is monitored throughout labour?

Answer 6

• maternal observations
• abdominal palpation
• vaginal examination
• liquor monitoring
• fetal heart auscultation
• uterine muscle contractions palpation
• external signs

Question 7

What is a vertex presentation?

Answer 7

• cephalic (head first) presentation, with the occiput (posterior frontanelle) leading
• most common

Question 8

What is Station?

Answer 8

• the term used to describe the descent of the head
• 0- head is at level of ischial spine

Question 9

What are the mechanisms of labour?

Answer 9

• descent
• fetus descends into pelvis
• engagement
• largest diameter of head fits into largest diameter of pelvis
• flexion
• neck flexes, chin to chest
• internal rotation of the head
• head turns 90° from occiputo-transverse to occiputo-anterior position
• crowning and extension of the head
• largest diameter of head is through narrowest part of pelvis + fetal neck extends
• restitution
• head rotates medially in line with shoulders
• internal rotation of the shoulders + external rotation of the head
• shoulder move from transverse to anterior-posterior position
• lateral flexion
• downward delivery of anterior shoulder + then upward delivery of posterior shoulder

Question 10

What are differnt types of analgesia used in labour?

Answer 10

• breathing, maternal position, massage, TENS
• paracetamol, dihydrocodine
• Entenox (nitrous oxide + oxygen)
• opiods (morphine, diamorphine, pethidine)
• remifentinal- patient controlled medication
• epidural