Normal and Abnormal Labour Flashcards
Define Labour
The process by which the products of conception are expelled from the uterine cavity after 24 weeks gestation.
Define the boundaries of the 1st stage of labour
Regular uterine contractions- full dilatation of the cervix
Define the boundaries of the 2nd stage of labour
Full dilatation of the cervix- delivery of the baby
Define the boundaries of the 3rd stage of labour
Delivery of the baby- delivery of the placenta
What processes are involved in the stage pre-labour?
Remodelling of the cervical connective tissue and preparation of the myometrium?
Descibe the preparation of the myometrium for labour
Increased gap junction formation
Prostaglandin production
Increased PG/oxytocin receptors
Influx of inflammatory cells
What is thought to be the trigger for labour?
Local progesterone withdrawal
Pro-contractile factors and decreased suppression of uterine actvity
What are Braxton-Hicks contractions?
Infrequent low intensity contractions during pregnancy
What happens to myometrial fibres during labour?
They shorten
What happens to lower uterine segment during labour?
Stretches, thins and the junction between the upper and lower segment rises (retraction)
Where do contractions begin?
The left side of the uterine fundus
Which shape of pelvis is most favourable for labour?
Gynecoid
What is the purpose of the sutures on the foetal skull?
Allow bones to move and overlap during labour (moulding) reducing diameter of foetal skull
Describe the motion of the baby?
Descent, flexion, internal rotation, extension, crowning, restitution, delivery
How is labour diagnosed?
Regular painful uterine contraction producing effacement and dilatation of the cervix
Bloody stained mucus
Membrane rupture
Confirmed by vaginal examination
What position should the baby’s head be in during crowning?
flexed
How long should the 3rd stage of labour take?
5-10mins
>30 mins is abnormal, risk of PPH
State 3 signs of placental separation.
Show of blood, lengthening of umbilical cord, elecation of fundus
What types of analgesia/anaesthesia can be used in labour?
Support Massage/relaxation techniques Inhalational agents- entonox TENS Water immersion IM opiate analgesia (morphine) IM remifentanil Regional anaesthesia (epidural, spinal anaesthesia)
What are the complications of epidural anaesthesia?
Hypotension, dural puncture, headache, atonic bladder, backache
How do you assess progress in labour?
Cervical dilatation
Descent of presenting part
Signs of obstruction
Distance from ischium
At what point is delay suspected during the first stage of labour?
Nulliparous: <2cm dilatation in 4hrs or slowing in progress
What is assessed in a partogram?
Foetal heart Amniotic fluid Cervical dilatation Descent Contractions Obstruction/moulding Maternal observations
Risk factors for foetal hypoxia
Small for dates foetus pre/post dates Antepartum haemorrhage preelampsia diabetes meconium epidural analgesia vaginal birth after c-section sepsis induction/augmentation of labour
