Labour Flashcards
What are the modes of delivery?
Vaginal birth after C-Section (VBAC)
Elective repeat C-Section (ERCS)
Vaginal Birth
Assisted Vaginal Delivery
What are the risks associated with VBAC?
Uterine rupture, delivery-related (perinatal death)
What are the indications for assisted vaginal delivery?
Slow progress in 2nd stage
Maternal exhaustion
To avoid raised ICP/BP
Presumed fetal compromise
What are the indications for induction of labour?
Agreed that the fetus/mother will benefit from a higher probability of a heathy outcome than if birth is delayed
Only considered when vaginal delivery is felt to be appropriate
Prolonged pregnancy: 41-42weeks past due date increases risk of perinatal mortality due to decreased placental function
Intrauterine growth retardation
PPROM/pre-labour rupture of membranes
Antepartum haemorrhage
Maternal hypertension or diabetes
Poor obstetric history
Intrauterine death
Maternal request
What are the contraindications of induction of labour?
ABSOLUTE: Acute fetal compromise Unstable lie Placenta praevia Pelvic obstruction RELATIVE: Previous C-section High parity Prematurity Breech
When should a membrane sweep be offered?
Prior to formal induction of labour women should be offered a vaginal examination for membrane sweeping
Nulliparous: 40-41 weeks Parous: 41 weeks
What are the components of a Bishop Score? What does the score help with?
Each given a score 0-3: Dilatation Length of cervix Station Position of cervix Consistency Helps determine whether IOL needed 0-5 unfavourable- IOL likely needed 6-13 favourable- Spont labour likely
What are the methods used to induce labour?
- Stretch & sweep: Release membranes from lower segment of the uterus & release prostaglandins for spont labour
- Prostaglandin: Cervical priming with prostaglandin inserted into the posterior fornix, multiple doses may be required
- ARM: With/without Oxytocin, favourable cervix (Bishop >5), some uterine activity, aseptic technique
What are the complications of induction of labour?
- Fetal distress
- Precipitate delivery
- Failure: Operative delivery
- Uterine hypertonia with possible rupture: >7contractions/15mins
- Amniotic fluid embolus
- Systemic effects: N&V, diarrhoea
Describe the mechanism of labour
As the foetus descends through the pelvis, soft tissue and bony structures exert pressures which lead to
descent through to the birth canal. In normal
labour the head engages into the pelvis in the left or
right occipito-anterior position
What are the stages of labour?
1: From onset of established labour (4cm) to full dilatation of the cervix (10cm)
2: From full dilatation to birth of the baby
3: From birth of the baby to expulsion of the placenta & membranes
What is included in the first stage of labour?
oConcerned with the opening of the cervix (usually women dilated a minimum of 2cm/4hours
oDescent of the baby’s head (in relation to the ischial spines of the pelvis- station of the head, also assessed on abdo palpation by how many 5ths of the baby’s head can be felt)
oBoth encouraged by women mobilising- walking & upright position in stage 1 reduce duration of labour, need for epidural, risk of C-section
Define multigravida & primigravida
M: Cervical dilatation <2cm in 4hours or slowing down of progress
P: Cervical dilatation <2cm in 4hours
How is slow progress of labour managed?
1: ARM
2: Syntocinon infusion
What is included in the second stage of labour?
oPASSIVE: Full dilatation of the cervix prior to/in the absence of involuntary expulsive contractions
oACTIVE: Expulsive contractions/active maternal effort with a full dilatation of the cervix
Once fully dilated the head moves down the pelvis & applies pressure to the pelvic floor causing the urge to push
What is included in the third stage of labour?
oDelayed cord clamping: Waiting for the cord to stop pulsating >1min reduced the risk of anaemia in babies
oActive management: Routine use of uterotonic drugs- Syntometrine, controlled cord traction- reduces risk of post-partum haemorrhage
oPhysiological management: No routine uterotonic drugs, no late clamping, delivery of placenta by maternal effort
What is ‘breech’ position? What are the different types?
In utero fetal position that leads to the buttocks being delivered first. 3% incidence
Frank/extended= 65%
Complete/flexed= 10%
Incomplete/footling= 25%
How is labour monitored?
Partogram: Pictorial record of labour
Charts: Cervical dilatation & descent of the head, frequency of contractions, fetal HR, liquor colour, maternal obs
How is breech position managed in the antenatal phase?
Vaginal breech delivery
C-Section
External cephalic version (36-37weeks)
What are the contraindications of external cephalic version?
Absolute: Placenta Praevia Uterine malformation Rupture membranes Multiple pregnancy Abnormal CTG Relative: Previous C-Section Active labour Pre-eclampsia Oligohydramnios Fetal abnormality Hypertension of fetal heart Maternal cardiac disease
At what dates are twins delivered?
- Dichorionic diamniotic: 37-38weeks
- Monochorionic diamniotic: 34-37weeks
- Monochorionic monoamniotic: 34weeks C-Section
What care is given in labour?
Eating & drinking: Encourage drinking throughout, light meals when desired
Bladder care: Encourage to pass urine regularly, may need a catheter (epidural)
Obs: Vital signs, urine analysis, vaginal loss (colour of liquor, fresh blood) contractions
Analgesia
Fetal monitoring: Identify hypoxia before sufficient enough to lead to damaging acidosis & long-term neuro adverse effects
What analgesia can be given in labour?
Pharmacological: Paracetamol, gas&air, epidural, opiates (Diamorphine)
Non-pharmacological: Water, mobilise, massage, relaxation & breathing
What instruments are used in an assisted vaginal delivery?
Rotational/traction forceps Vacuum extraction (Ventouse)
What are the indications for an operative vaginal delivery?
-Fetal compromise
-Maternal fatigue/exhaustion
-Reduce effects of 2nd SOL in those with a medical condition
-Prolonged 2nd stage of labour:
>1hr passive phase & 1hr active pushing in M
>2hr passive phase & 1hr active pushing in P
What are the prerequisites for an operational vaginal delivery?
- Head <1/5th palpable
- Cervix fully dilated w/ROM
- Exact position of the head determined
- Pelvis adequate
- Consent from mother
In operational delivery what are high failure rates associated with?
- High Maternal BMI >30
- Estimated fetal weight >4kg or clinically big baby
- OP position
- Mid-cavity delivery when >1/5ths of head palpable
Describe a forceps delivery
Traction applied along flexion point 2cm in front of occiput Wrigley's= C-section Kielland's= Rotational delivery More successful than ventouse Post: Diclofenac & Paracetamol
What are the complications of a forceps delivery?
Signif maternal genital trauma
RARE: Facial nerve palsy, skull#, orbital injury, intracranial haemorrhage
Describe a ventouse delivery
Cup held in place by atmospheric pressure on the cup against the negative pressure created
NOT used at <34weeks
Post: Diclofenac & Paracetamol
What are the complications of a ventouse delivery?
Intracranial & retinal haemorrhage, cephalohaematoma, subgaleal haemorrhage, neonatal jaundice, scalp lacteration & avulsion
In what instance are both ventouse & forceps contraindicated?
Before full dilatation
Define augmentation
The process of stimulating the uterus to increase the frequency, duration & intensity of contractions after the onset of spontaneous labour
What drugs can be used to augment labour?
Oxytocin
Prostaglandin
What are the potential SE of augmentation?
Uterine hyperstimulation
Fetal distress
Uterine rupture
How is prolonged pregnancy defined?
Pregnancy beyond 42weeks
What is prolonged pregnancy associated with?
Fetal: Inc risk of stillbirth, Inc risk of death in first year of life
Maternal: Obstructed labour, perineal damage, C-Section, infection, postpartum haemorrhage, instrumental delivery
What happens if a woman wants to continue with a prolonged pregnancy?
Twice weekly CTG
Weekly USS for liquor vol assessment >3cm at deepest pool (less is a sign of placental insufficiency)
Doppler of umbilical arteries
What is the most appropriate mode of delivery:
30yo primigravida with an epidural in situ & delayed 2nd stage of labour has been pushing for 2hours & is exhausted. OE the fetus is OA at station +2. CTG is normal
Non-rotational forceps if more than 3contractions required to deliver the baby then convert to a C-Section
Spinal/epidural/pudendal nerve block required
What is the most appropriate mode of delivery:
26yo woman in antenatal clinic is 39w. She had a previous classical C-Section
Elective C-Section
What is the most appropriate mode of delivery:
27yo is in labour & fully dilated. OE a face presentation is felt with the chin posteriorly
Emergency C-Section: Chin posteriorly means vaginal delivery is not possible due to the large occiput
Chin felt anteriorly then normal delivery
What is the most appropriate mode of delivery:
32yo woman fully dilated for 1hr & pushing for a further hour. The baby is not yet delivered despite good maternal effort. OE vertex presentation & OP position
Kielland’s rotational forceps: Used to turn the baby to an OA position & traction to deliver the baby.
What is the most appropriate mode of delivery:
29yo woman is dilated at 10cm. OE there is an OA presentation w/flexed head. One previous LSCS.
Normal vaginal delivery
OA w/flexed head is favourable position for vaginal delivery
