Normal birth Flashcards
Which weeks gestation are considered as ‘normal’ for birth?
37-42 weeks
What three main things occur during the passive first stage of labour?
Irregular contractions
Rupture of membranes/some cervical change (effacement/dilatation)
Bloody mucus show
Which stage of labour involves regular painful contractions and progressive cervical dilatation from 4cm?
Active first stage
How much cervical dilation should occur per hour in the active first stage?
0.5cm
Which non-pharmacological pain relief methods can be used in labour?
Breathing and relaxation
Massage
Water
What are the 2 main pharmacological pain relief methods in labour?
Entonox (nitrous oxide, ‘gas and air’)
Opiods
What is the regional pain relief used in labour?
Epidural
Which stage of labour does the head become visible?
Active second stage
Which stage of labour does the cervix become fully dilated?
Passive second stage
For a first time mother, how long of active second stage labour is the cut of for a diagnosis of delay?
2 hours
Which uterotonic drug is given to manage the third stage of labour?
Oxytocin
To prevent PPH
Name 4 serious postpartum complications
PPH
Infection
VTE
Pre-eclampsia
What is the average length of the first stage of labour in a first time mum?
8 hours
What are the 3 main causes of a delayed labour?
3 Ps
power (contractions)
pathway (pelvis)
passenger (baby)
What are some mechanisms that may account for labour starting?
Increased maternal/fetal cortisol
Fetal lung maturation
Decrease in progesterone and increased oestrogen and oxytocin and prostaglandins
What is the function of the mucus plug coming away at the start of labour?
Deters microbes
Which segment of the uterus is active (upper or lower)?
Upper is active
Which ion is the key regulator for contractions to occur?
Calcium
Apart from ions, what is the key to the strength and frequency of contractions?
Hormones
Which hormones are essential for the progression of labour?
Prostaglandins Corticotropin releasing hormone Estrogens Progesterone Endorphins Adrenaline Oxytocin
How does positive feedback help during labour?
Baby pushes against cervix, causing it to stretch
This causes reflex to brain which stimulates oxytocin release
Oxytocin makes uterus contract more
How does oxytocin have an effect on uterine contractions?
Increases contractions
because oxytocin stimulates the release of prostaglandins (these stimulate contraction of the uterus)
Can also directly induce contraction by activating calcium channels
Which hormone is used artificially to speed up labour?
Oxytocin
What causes the pain of labour?
Distension of the cervix
Reduced oxygen and blood supply during uterine contractions
Ischaemia from tissue damage (stretching/tearing) in the pelvis and perineum
What must happen for the head to pass through the pelvis most easily?
Head must ROTATE
Why are vertical positions in labour helpful?
May benefit from gravity
What is good about lateral positions in labour?
Positively affects maternal and fetal circulation
What does most of the ‘waters’ contain at term?
Fetal urine
What colour of the ‘waters’ is concerning?
Either green (meconium) Fresh red (haemorrhage)
What is a normal fetal heart rate?
100-160 bpm
What effect does each contraction have on the fetus?
Can cause head/cord compression and less placental perfusion
Causes a mild hypoxic event
What methods are there to assess the fetal heart?
- Pinard
- Hand held doppler
- CTG (for high risk)
What percentage of women having a vaginal birth will have some degree of perineal trauma?
85%
