Case 14 A 30-year-old woman with a
postdated pregnancy
Mrs Timmons is a 30-year-old woman in her first pregnancy.
It has been an uncomplicated pregnancy but her baby was
due 7 days ago and she comes to the antenatal clinic to
discuss what to do.
What should happen at the clinic?
• Routine antenatal assessment: blood pressure (BP) and
urinalysis
• Abdominal examination including symphysiofundal
height (SFH), presentation of fetus and auscultation of
fetal heart
• Enquire about general well - being and fetal
movements
She tells you that she feels tired but well. She has been
feeling plenty of normal movements from the baby. Her
blood pressure is 120/80mmHg which is normal for her and
her urinalysis is negative. Her baby feels well grown (SFH is
39cm), is in a cephalic presentation and the fetal heart is
clearly heard. She asks you when you might induce her
labour.
What do you say?
This seems to be a ‘ low risk ’ pregnancy and therefore
national guidelines suggest induction of labour between
41 and 42 weeks. This maximizes the rate of spontaneous
labour, decreases perinatal mortality resulting from postmaturity but does not increase the caesarean section rate
from failed induction of labour.
She may wish to have a vaginal examination and membrane sweep as there is good evidence that this increases
the spontaneous labour rate in postdated pregnancies.
Performing a membrane sweep increases the discomfort
of the examination and often causes a small amount of
bleeding.
What will you tell her about your
vaginal examination findings?
When a vaginal examination is performed before labour
the findings are, by convention, assigned a score known
as a Bishop ’ s score which gives information about the
favourability of the cervix in relation to labour (Table
14.1 ).
She accepts a vaginal examination and membrane sweep.
Her Bishop’s score is 5 and you book a date for induction at
term +10. She asks you what will happen when she attends
for induction.
What information would you discuss
with her?
She will be admitted to an antenatal ward. The baby ’ s
heart rate will be monitored using cardiotocography
(CTG) to ensure the baby is well. She will have a vaginal
examination and prostaglandin (PGE2) tablets will be
inserted into the vagina. These tablets soften and shorten
the cervix in preparation for labour.
If she is not labouring she will be given another dose
of prostaglandins after 6 – 8 hours. A maximum of 6 mg
PGE2 tablets will be used. If she does not labour she will
have her waters broken (amniotomy) and be started on
oxytocin to stimulate her contractions.
She understands and is happy with this plan. At 23.30 that
evening she calls the labour ward to say she thinks she is
having contractions.
What questions will you ask her?
• When did the contractions start?
• How often are they coming and how long do they last?
• Does she have any vaginal bleeding or discharge?
• Does she think her waters have broken?
• Is she feeling the baby moving?
• Has she tried anything for the pain and is she still
coping at home?
Obstetrics and Gynaecology: Clinical Cases Uncovered.
By M. Cruickshank and A. Shetty. Published 2009 by Blackwell
Publishing. ISBN 978-1-4051-8671-1.98 Part 2: Cases
PART 2: CASES
Mrs Timmons says she has been having pains roughly every
10minutes since she went home from the antenatal clinic
but now they are coming every 5minutes. She thinks they
last about 1minute. She had paracetamol earlier but is not
coping well with the pains now. She has no vaginal bleeding
or discharge and the baby is moving normally. She is keen
to come to hospital. You advise her to come to the labour
ward.
What will you do when she arrives?
• Perform a CTG
• Assess the contractions for timing and duration
• Perform abdominal and vaginal examinations
She arrives at 00.30. She looks sore and seems to be
contracting 3:10minutes. The CTG is reassuring. Examination
reveals that the baby is in a cephalic presentation. Vaginal
examination shows that the cervix is 5cm dilated and fully
effaced. The vertex of the fetal head is 1cm above the
ischial spines (Vx 0–1) and the position of the fetal head is
thought to be occipito-posterior.
What will be the plan for Mrs Timmons’
labour?
• Adequate analgesia
• Intermittent auscultation of the fetal heart
• Repeat vaginal examination in 4 hours to ensure
progress
Mrs Timmons has intramuscular morphine for pain. The fetal
heart rate remains reassuring and she is reassessed after
4hours. Unfortunately, she is still 5cm dilated. Since the
morphine her contractions have decreased to 1:10minutes
(Fig. 14.1; Box 14.1).
Table 14.1 Bishop’s score. A Bishop’s score <7 is considered
unfavourable and usually indicates a more difficult induction
process. Scores ≥7 indicate a favourable cervix.
Cervical
feature
Score
0 1 2 3
Dilatation (cm) <1 1–2 2–4 >4
Length (cm) >4 2–4 1–2 <1
Consistency Firm Average Soft –
Station –3 –2 –1/0 +1 +2
Position Posterior Mid/anterior – –
10
Cervical dilation (cm)
9 8 7 6 5 4 3 2 1 0
Time (hours)
Normal labour
Four hour action line
Mrs Timmons
Figure 14.1 Partogram to assess progress in labour.
Box 14.1 The partogram
The partogram is a graphical representation of progress in
labour and of maternal and fetal observations. The excerpt
in Fig. 14.1 only shows cervical dilatation but in reality
it charts maternal pulse, BP and temperature every
15minutes. Fetal heart rate is also noted every 15minutes.
Frequency and strength of uterine activity is recorded every
30minutes as is the colour of any liquor draining and any
drugs administered. Cervical dilatation, and descent and
position of the fetal head are marked down after each
vaginal examination.
The partogram therefore provides an ‘at a glance’ guide
to the progress of labour and the maternal and fetal
condition.Case 14 99
PART 2: CASES
What is the plan now?
Perform an amniotomy to attempt to improve the
uterine activity. Reassess in 2 hours to ensure progress.
An amniotomy is performed and the liquor is clear. Mrs
Timmons’ contractions remain 1:10minutes and she is able
to sleep on and off during the next 2hours. She is
reassessed at 06.30 and found to be 5cm dilated and the
baby is felt to be still occipito-posterior (Fig. 14.2).
What will you tell Mrs Timmons?
Her progress in labour is slower than would be expected.
This is probably because her contractions are suboptimal
(we would aim for 4 – 5 moderate to strong contractions
in 10 minutes). The baby ’ s head is in a malposition
(occipito - posterior) which makes labour less efficient
(Box 14.2 ).
What intervention would
you recommend?
As her uterine activity is now virtually non - existent, augmentation of her labour with oxytocin is recommended
and reassessment of cervical progress 4 hours after good
contractions.
She accepts augmentation of her labour. She is commenced
on a CTG which is reassuring and oxytocin is commenced.
The oxytocin is gradually escalated and 90minutes later she
is contracting well with four moderate contractions in
10minutes. She is now very sore and requests an epidural.
What information should you give her?
The anaesthetist will explain the procedure to her and
make sure she understands it. She will then be asked to
10
9 8 7 6 5 4 3 2 1 0
Time (hours)
Amniotomy
Cervical dilation (cm)
Normal labour
Four hour action line
Mrs Timmons
Figure 14.2 Partogram to illustrate slow progress in labour.
Box 14.2 Progress in normal labour
Active labour is diagnosed in the presence of painful
regular uterine activity once the cervix has reached 4cm
dilated and is fully effaced. In 1955, Friedman studied 200
normal women and determined that the slowest 10%
progressed at 1cm/hour in the active phase of labour.
These figures are extremely small and were taken a long
time ago and since then mothers and babies have
changed significantly. Additionally, these data have not
been replicated in other trials and the recent NICE
guideline on intrapartum care recommends using
2cm/4hours as the minimum acceptable progress in the
active first stage of labour. NICE apply this definition of
delay in first stage to either primigravid or parous women.
However, it should be borne in mind that labours in
multiparous women are usually significantly faster than in
primigravidae and if they are progressing slowly this
should alert the attendants to the fact that something may
be wrong. The WHO recommend a 4-hour action line on
the partogram which indicates when labour is progressing
at a rate 4hours more slowly than expected. If this line is
crossed once active labour is diagnosed, some action
should be taken to accelerate or end labour in order to
minimize risk to mother and baby.
either lie on her side or sit up and curve her back out.
The anaesthetist will put some local anaesthetic in the
skin and muscle of her back and then put a needle in her
back to find the epidural space. A fine flexible tube is
pushed through this needle, the needle is then removed.
Drugs (local anaesthetic and analgesics) are given through
the tube which is known as a catheter.
The epidural usually works within 10 – 20 minutes. It
remains in place until after she has delivered her baby. A100 Part 2: Cases
PART 2: CASES
measured amount of drugs may be given each hour or
her epidural may be topped up using a syringe. Occasionally, epidurals do not give good pain relief. If this happens
the epidural may need to be repositioned, a different
combination of drugs used or the epidural may need to
be replaced.
Advantages of an epidural
• Epidurals nearly always give good pain relief
• Because the drugs used are injected into the women ’ s
back, very little goes through to the baby
Disadvantages of an epidural
• The woman ’ s blood pressure may drop, which can
make her feel sick and dizzy. If this happens she will be
asked to turn onto her side, she may be given fluid
through a drip and might possibly need an injection to
bring her blood pressure up again.
• Her mobility is likely to be limited.
• She may not be able to pass urine. If this happens a
catheter will be used to empty her bladder.
• She may feel itchy; sometimes the combinations of
drugs used can be altered to help relieve this.
• A small number (about 1%) of women develop a
severe headache following an epidural (dural puncture
headache). This can usually be effectively treated fairly
quickly, but it can sometimes last for a number of weeks.
• She may develop a high temperature which could lead
to an abnormally fast heart rate in the baby. This may
lead to her and/or her baby being treated with antibiotics
and screened for infection.
• There is an increased risk of the baby being delivered
by forceps or ventouse.
She is seen by the anaethetist and her epidural is sited. It
works well and there are no further problems until she is
reassessed at midday as planned. Her cervix is now 9cm
dilated and the baby has turned to a much more favourable
occipito-anterior position, it has also descended through the
pelvis and the fetal head is now 1cm below the ischial
spines (Fig. 14.3).
What is the plan now?
She has made good progress since she was commenced
on oxytocin so labour should be allowed to continue
normally. Continue oxytocin and reassess in 1 hour when
it is expected that she will be fully dilated.
She is reassessed after another hour and is fully dilated; the
CTG remains reassuring. The plan is to allow a further hour
for descent of the fetal head and then allow active pushing
to try to effect delivery. Mrs Timmons is happy with this
plan.
You are called to see her 2 hours later when she has
been pushing for 1 hour but the baby is not delivered
(Box 14.3 ).
What factors are important in deciding
what to do?
Maternal factors
• Is she well? Are her pulse, BP and temperature all
normal?
• Is she comfortable with her epidural?
• Have the contractions remained good and is she
pushing well?
• What does she want to do?
10
Cervical dilation (cm)
9 8 7 6 5 4 3 2 1 0
Time (hours)
Normal labour
Four hour action line
Mrs Timmons
Amniotomy
Oxytocin
augmentation
commenced
Figure 14.3 Partogram illustrating good progress with oxytocin augmentation.Case 14 101
PART 2: CASES
Fetal factors
• Is the CTG reassuring?
• Is the vertex advancing?
• What are the findings on vaginal examination?
Mrs Timmons’ observations are all normal, she is
comfortable and she has been pushing well with good
contractions but she is exhausted and keen for the baby to
be delivered. The CTG shows a few early decelerations but is
otherwise reassuring for second stage labour. The vertex
was advancing and is just visible at the height of the
contractions but has not moved much in the last 20minutes.
There is no head palpable in the maternal abdomen and
vaginal examination confirms that the cervix is fully dilated,
the fetal head is in an occipito-anterior position and it is at
the ischial spines plus 2cm (Vx 0 + 2).
What will you tell her now?
The options are assisted vaginal delivery or to continue
actively pushing to try for a spontaneous vertex delivery.
It should be quite safe to deliver the baby with forceps or
a ventouse in the delivery room if she wishes.
Mrs Timmons agrees to assisted vaginal delivery.
What preparations are required to
deliver the baby?
The anaesthetist should be called to top up her epidural
for delivery. Mrs Timmons should have her legs placed
in the lithotomy position. She should have the vulva
cleaned and draped and the bladder should be emptied
using an in – out catheter.
The forceps or ventouse should be applied with contractions and the position of the instrument needs to be
checked. Traction should then be applied with contractions until the head is crowning and then a right mediolateral episiotomy should be made to protect against
third or fourth degree perineal tears.
Once the head is delivered the instrument should be
removed to allow the head to restitute prior to delivery
of the baby ’ s body. Once the baby is delivered, the placenta can be delivered by continuous cord traction and
the episiotomy repaired.
She delivers a male baby weighing 3.45kg in good condition
by ventouse. The episiotomy is repaired and her total
estimated blood loss is 350mL. Mrs Timmons is very happy
with the outcome and will be fit for discharge in a day or
two.
Box 14.3 Second stage of labour
NICE guidelines divide second stage into a passive and an
active phase. Passive second stage of labour is defined as
the finding of full dilatation of the cervix prior to or in the
absence of involuntary expulsive contractions. The active
second stage of labour commences at full dilatation when
the baby is visible, there are expulsive contractions or
other signs of full dilatation or active maternal effort is
commenced in the absence of expulsive contractions (most
commonly in the presence of epidural analgesia). Delivery
will usually have occurred after 3hours of active second
stage in primigravidae and after 2hours in parous women.
To allow for delivery within these time frames it is
recommended that referral regarding delay in second
stage be made to medical staff after 2hours in
primigravidae and 1hour in parous women.102 Part 2: Cases
PART 2: CASES
CASE REVIEW
Mrs Timmons, a 30 - year - old primigravida with an
uncomplicated antenatal course, was due to be induced
at T + 10 days for the indication of postdates. She had a
membrane sweep some days prior to the planned induction and actually went into labour spontaneously before
her date for induction. Progress in labour was slow, and
augmentation was performed initially with an artifical
rupture of membrances and then an oxytocin infusion.
She had morphine and followed by an epidural for pain
relief. She reached full cervical dilatation and after allowing time for the head to descend, she commenced active
pushing. However, delivery did not occur spontaneously
and an instrumental delivery was successfully performed
for the indication of maternal exhaustion and prolonged
second stage.
Slow progress is common in labour, especially in primigravidas. Except in highly multiparous women or those
with previous caesarean sections when augmentation in
labour is relatively contraindicated, labour can be augmented with oxytocin - like compounds to try to achieve a
vaginal delivery providing there are no concerns about
maternal or fetal well - being.
Augmenting labour in this way will reduce the numbers
of caesarean sections performed for lack of progress. It is
necessary to monitor both mother and baby carefully
during this process as oxytocin augmentation carries some
additional risks to both, over and above normal labour.
Continuous fetal heart rate monitoring (CTG) is required
because of the risk of fetal distress secondary to uterine
hyperstimulation.
Assisted vaginal delivery, when performed by appropriately trained individuals, is safe and eliminates the significant risks associated with caesarean section when the fetal
head is very low in the maternal pelvis.
KEY POINTS
• Induction of labour is offered to women with a low risk
pregnancy at 41–42 weeks’ gestation
• A membrane sweep should be offered to women at term
to increase their chances of labouring spontaneously
• Bishop’s score is generally used to determine the
‘ripeness’ or ‘favorability’ of the cervix, with scores of 6 or
less suggesting an unfavourable cervix
• With an unfavourable cervix, induction of labour with
vaginal prostaglandins is indicated
• Labour can be augmented when there is slow progress
with an artificial rupture of membranes +/– oxytocin
infusion. The frequency of uterine contractions and the
fetal heart should be carefully monitored while on the
oxytocin infusion
• Transcutaneous electrical nerve stimulation (TENS),
Entonox, morphine and an epidural are all options for
pain relief in labour
• Prior to performing an instrumental delivery, care must be
taken to ascertain the position and station of the head
vaginally, and to confirm that no more than one-fifth of
the head is palpable abdominally. Where the head is in a
position other than occipito-anterior (e.g. occipitoposterior or transverse), rotation to the occipito-anterior
position can be performed either manually, with a
ventouse or by rotational forceps and delivery completed
Further reading
NICE Clinical Guideline . Intrapartum care: management and
delivery of care to women in labour. CG55, September 2007.
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