Labour and delivery Flashcards
What is labour?
The progressive effacement and dilatation of the cervix in the presence of regular uterine contractions
What is meant by delivery?
Expulsion of the foetus and placenta
What is meant by ‘show’?
Cervical mucus plug
What is SROM?
Spontaneous rupture of membranes, can precede labour.
Breaking of water
What is ARM?
Artificial rupture of membranes, this is when we induce labour.
What is meant by gravidity and parity?
Gravidity= no. Of pregnancies including present
Parity= the state of giving birth
(The no. Of births >24 hours, >500g)
It gets complicated when the woman has twins, as this is only one gravidity but 2 parity’s
When do contractions occur in labour?
Contractions are rhythmic and occur every 3-4 minutes in early labour and 2-3 in advanced labour
What is meant by the lie of the baby and what are the types?
Relationship of the fetal long axis to that of the mother
Long, oblique, transverse
What is meant by the presentation?
This is the part of the foetus which is lowermost in the uterus, normally the head.
How can you work out the position of the baby?
Position is foetus dominator in relation to maternal pelvis
Work out the position by looking at the fontanelle, the posterior fontanelle tends to be in a v shape
The anterior is more of a diamond
When does labour normally occur?
Between 37 and 42 weeks gestation
What are the 3 stages of labour?
First stage- onset of labour (true contractions) until 10cm cervical dilatation
Second stage- 10cm dilatation until delivery of baby
Third stage- delivery of baby and placenta
What are the phases of the first stage of pregnancy?
Latent phase- from 0 to 3cm dilation of the cervix, this progresses at around 0.5cm per hour, they are irregular.
Active phase- from 3cm to 7cm dilation of the cervix, this progresses at around 1cm per hour, regular contractions
Transition phase- from 7cm to 10cm dilation of the cervix, this progresses at around 1cm per hour and there are strong and regular contractions.
What are braxton hicks contractions?
Occasional irregular contractions of the uterus (second and third trimester). They don’t indicate labour, they are temporary and irregular tightening or mild cramping in the abdomen.
What are the signs of labour?
. Show (mucus plug from the cervix)
Rupture of membranes
Regular, painful contractions
Dilating cervix on examination
The first stage is also split into first stage and second stage, what is meant by this?
Latent first stage is when there are both…
Painful contractions
Changes to the cervix, with effacement (getting thinner) and dilatation up to 4cm
Established first stage is when there are both
Regular and painful contractions
Dilatation of the cervix from 4cm onwards
What is the definition of prematurity?
It is defined as birth before 37 weeks gestation
What is meant by babies being non viable?
Babies are considered non viable below 23 wekeks gestation
When would you offer full resuscitation to a premature baby?
From 24 weeks onwards
What does the WHO classify prematurity as?
Under 28 weeks: extreme preterm
28-32 weeks: very preterm
32-37: moderate to late preterm
What prophylaxis can be given to prevent preterm labour?
Vaginal progesterone
Cervical cerclage
How does progesterone work for prophylaxis of preterm labour?
Progesterone can be given vaginalis or by a pessary, progesterone has a role in maintaining pregnancy and preventing labour by decreasing the activity of the myometrium and preventing the cervix remodelling in preparation for delivery.
What is cervical cerclage?
Involves putting a stitch in the cervix to add support and keep it closed, it involves general or spinal anaesthetic, the stitch is removed when the woman goes into labour or reaches term.
Who is a cervical cerclage offered to?
Offered to a woman with cervical length less than 25mm on vaginal US between 16 and 24 weeks who have had previous premature birth or cervical trauma (colposcopy/cone biopsy).
What is preterm prelabour rupture of membranes?
Is where the amniotic sac ruptures releasing amniotic fluid, before the onset of labour and in a preterm pregnancy (under 37 weeks gestation).
How do you diagnose preterm prelabour rupture of membranes?
Speculum examination revealing pooling of amniotic fluid in the vagina, if there is doubt then investigations can be carried out…
Insulin like growth factor binding protein 1 (IGFBP-1) is a protein present in high concentrations in amniotic fluid, can be tested on vaginal fluid.
Placental alpha micro globin 1 is similar
How should you manage preterm prelabour rupture of membranes?
Prophylactic antibiotics should be given to prevent the development of chorioamnionitis.
NICE recommends erythromycin 250mg four times daily for ten days or until the labour is established
Induction of labour may be offered from 34 weeks to initiate labour
What is preterm labour with intact membranes?
Involves regular painful contractions and dilatation without the rupture of the amniotic sac.
How do you diagnose preterm labour with intact membranes?
Speculum examination to assess for cervical dilatation, without rupture of the amniotic sac
Less than 30 weeks gestation, clinical assesment alone is enough to offer management of preterm labour
More than 30 weeks gestation, a trans vagina ultrasound can be used to assess the cervical length (if cervical length is less than 15mm then management of preterm labour can be offered, if cervical length is more than 15mm then preterm labour is unlikely)
What are the management options for preterm labour?
Fetal monitoring (CTG or intermittent auscultation)
Tocolysis with nifedipine
Maternal corticosteroids (these are offered before 35 weeks gestation to reduce neonatal morbidity and mortality)
IV mag sulfate can be given before 34 weeks and helps protect the baby’s brain
Delayed cord clamping or cord milking can increase the circulating blood volume and haemoglobin in the baby at birth
How do antenatal steroids work and what would an example regime be?
Giving the mother (<35 weeks gestation) can help to develop the fetal lungs and reduce respiratory distress syndrome after delivery
An example regime would be two doses of intramuscular beta methasone 24 hours apart
When and why would you give magnesium sulfate?
Given to mothers within 24 hours delivery of premature baby of less than 34 weeks gestation, it is given as a bolus, followed by an infusion for up to 24 hours or until birth.
Helps protect the fetal brain during premature delivery, it reduces the risk and severity of cerebral palsy.
Mothers who have been given IV magnesium, need close monitoring for magnesium toxicity at least four hourly, this involves observations and reflexes.
What should you look out for with magnesium toxicity?
Reduced RESP rate
Reduced blood pressure
Absent reflexes
When May induction of labour be used?
Prelabour rupture of membranes Fetal growth restriction Pre eclampsia Obstretic cholestasis Existing diabetes Intrauterine fetal death
When patients go over due date- between 41 and 42 weeks gestation
What is the bishop score?
Scoring system which is used to determine whether to proceed with induction of labour.
A score of 8 or more predicts there will be a successful induction of labour.
What is oral mifepristone and when is this used?
It is an anti progesterone and is used to induce labour where intrauterine fetal death has occurred.
What are the options for inducing labour?
Membrane sweep (finger into the cervix, to stimulate the cervix and begin the process of labour) should produce onset of labour within 48 hours.
Vaginal prostaglandin E2 (dinoprostone) involves inserting a gel, tablet, pessary into the vagina this slowly releases local prostaglandins over 24 hours, stimulates the cervix and uterus to cause the onset of labour
Cervical ripening balloon
Artificial rupture of membranes with oxytocin infusion (only used when you can’t use vaginal prostaglandins or used when vaginal prostaglandins have already initiated the process.
Oral mifepristone (anti progesterone) plus misoprostol can be used to induce labour where intrauterine fetal death has occurred.
How do you monitor during the induction of labour?
Cardiotocography (CTG) assess fetal heart rate and uterine contractions before and during the induction of labour
Bishop score before and during the induction of labour to monitor progress
Most women will give birth within 24 hours of the start of induction of labour, the options when there is slow or no progress are?
Further vaginal prostaglandins
Artificial rupture of membranes and an oxytocin infusion
Cervical balloon ripening
Elective Caesarean section
The main complication of induction of labour with vaginal prostaglandins is uterine hyperstimulation, what is this?
This is where the contraction of the uterus is prolonged and frequent, causing fetal distress and compromise.
What is cardiotrocography/ electronic fetal monitoring?
Useful way of monitoring the condition of the foetus and the activity of labour
CTG can help guide decision making and delivery
Where are the transducers places in the abdomen to get the CTG readout?
One above the foetal heart to monitor the foetal heartbeat
One near the Fundus of the uterus to monitor uterine contractions
The one above uses Doppler
The one below uses ultrasound
What are the indications for continuous CTG monitoring in labour?
Sepsis Maternal tachycardia (>120) Significant meconium Pre eclampsia (BP >160/110) Fresh anterpartum haemorrhage Delay in labour Use of o to in Disproportionate maternal pain
What are the key features to look for on a CTG?
Contractions
Baseline rate
Variability (how the fetal heart rate varies up and down around the baseline)
Accelerations- where the fetal heart rate spikes
Decelerations- where the fetal heart rate drops
What are good signs on CTG?
Accelerations- good sign that the foetus is healthy, particularly when occurring alongside contractions of the uterus.
Baseline rate and variability is describes as reassuring, non reassuring and abnormal.
What is a concerning findings on CTG?
Deceleration- this indicates hypoxia, the fetal heart rate is slowing to conserve oxygen for vital organs
What are early depolarisations?
Gradual dips an recoveries in heart rate which correspond with uterine contractions, the lowest point of deceleration corresponds to the peak of the contractions. Early decelerations are normal and not considered as pathological.
What are late decelerations?
Gradual falls in the heart rate which start after the uterine contractions has already begun, there is a delay between the uterine contractions and the deceleration, the lowest point of deceleration occurs after the peak of the contraction.
