Maternal Care addresses all the common and important problems that occur during pregnancy, labour, delivery and the puerperium. It covers: the antenatal and postnatal care of healthy women with normal pregnancies, monitoring and managing the progress of labour, specific medical problems during pregnancy, labour and the puerperium, family planning, regionalised perinatal care
Maternal Care: Preterm labour and preterm rupture of the membranes
1. 5
Preterm labour
and preterm
rupture of the
membranes
Before you begin this unit, please take the PRETERM LABOUR AND
corresponding test at the end of the book to
assess your knowledge of the subject matter. You PRETERM RUPTURE OF
should redo the test after you’ve worked through THE MEMBRANES
the unit, to evaluate what you have learned.
5-1 What is preterm labour?
Objectives Preterm labour is diagnosed when there are
regular uterine contractions before 37 weeks of
When you have completed this unit you pregnancy, together with either of the following:
should be able to: 1. Cervical effacement and/or dilatation.
• Define preterm labour and preterm 2. Rupture of the membranes.
rupture of the membranes.
• Understand why these conditions are 5-2 What is preterm rupture
very important. of the membranes?
• Understand the role of infection in Preterm rupture of the membranes is diagnosed
causing preterm labour and preterm when the membranes rupture before 37 weeks,
rupture of the membranes. in the absence of uterine contractions.
• List which patients are at increased risk
NOTE Preterm rupture of the membranes (as
of these conditions. defined above) is sometimes called preterm,
• Understand what preventive measures prelabour rupture of the membranes in literature.
should be taken.
• Diagnose preterm labour and preterm 5-3 What is prelabour rupture
rupture of the membranes. of the membranes?
• Manage these conditions. Prelabour rupture of the membranes is
defined as rupture of the membranes for at
least one hour before the onset of labour in a
term pregnancy.
2. 118 MATERNAL CARE
5-4 How should you diagnose preterm membranes and placenta. Later these bacteria
labour if the gestational age is unknown? may colonise the liquor, from where they may
infect the fetus.
Preterm labour is diagnosed if the estimated
fetal weight is below 2500 g. The symphysis- Chorioamnionitis may cause the release
fundus height will be less than 35 cm. of prostaglandins which in turn stimulate
uterine contractions and cause the onset of
5-5 Why are preterm labour and preterm labour. Chorioamnionitis may also weaken the
rupture of the membranes important? membranes and lead to their rupture. If the
membranes have already been ruptured due to
Preterm labour and preterm rupture of the other causes, such as polyhydramnios, vaginal
membranes are major causes of perinatal bacteria can spread directly into the liquor. The
death because: longer the duration of ruptured membranes, the
1. Preterm delivery, especially before 34 weeks, greater the risk of chorioamnionitis. The risk
commonly results in the birth of an infant of infection is also increased by digital vaginal
who develops hyaline membrane disease examinations after rupture of the membranes.
and other complications of prematurity.
2. Preterm labour and preterm rupture of NOTE After delivery, the diagnosis of
chorioamnionitis can be confirmed by:
the membranes are often accompanied by
bacterial infection of the membranes and • Noting that the infant and placenta
placenta that may cause complications for have an offensive smell.
both the mother and the fetus. The mother • Noting that the membranes are cloudy.
and fetus may develop severe infection,
• Finding pus cells and bacteria on
which is life threatening
microscopic examination of the infant’s
gastric aspirate immediately after birth.
5-6 What is the commonest known
• Finding acute inflammation in the membranes
cause of preterm labour and preterm
and placenta on histology after delivery.
rupture of the membranes?
In many cases the cause is unknown, but Infection of the membranes and placenta
increasing evidence points to infection of the (chorioamnionitis) may occur with either intact
membranes and placenta as the commonest or ruptured membranes.
known cause of both preterm labour and
preterm rupture of the membranes.
5-8 What is the clinical presentation
of chorioamnionitis?
Infection of the membranes and placenta is the
Usually chorioamnionitis is asymptomatic
commonest recognised cause of preterm labour
(subclinical chorioamnionitis) and, therefore,
and preterm rupture of the membranes.
the clinical diagnosis is often not made.
However, the following signs may be present:
5-7 What is infection of the
1. Fetal tachycardia.
membranes and placenta?
2. Maternal pyrexia and/or tachycardia.
Infection of the membranes and placenta 3. Tenderness of the uterus.
causes an acute inflammation of the placenta, 4. Drainage of offensive liquor, if the
membranes and decidua. This condition is membranes have ruptured.
called chorioamnionitis. It may occur with
If any of the above signs are present, a diagnosis
intact or ruptured membranes.
of clinical chorioamnionitis must be made.
Bacteria from the cervix and vagina spread
through the endocervical canal to infect the
3. PRETERM LABOUR AND PRETERM RUPTURE OF THE MEMBRANES 119
NOTE There is no proof that daily white cell 2. Fetal factors:
counts or determination of C-reactive protein • A multiple pregnancy.
(CRP) are of any greater diagnostic value in • Polyhydramnios (both cause
making an early diagnosis of chorioamnionitis. overdistension of the uterus.)
• Congenital malformations of the fetus.
5-9 What factors may predispose • Syphilis.
a woman to chorioamnionitis? 3. Placental factors:
1. Rupture of the membranes. • Placenta praevia.
2. Exposure of the membranes due to • Abruptio placentae.
dilatation of the cervix.
NOTE Polyhydramnios, multiple pregnancy and
3. Coitus during the second half of
cervical incompetence cause preterm dilatation
pregnancy. of the cervix with exposure of the membranes
However, in many cases, the factors that result to the vaginal bacteria. This may predispose
in chorioamnionitis are not known. to chorioamnionitis. Polyhydramnios has
several causes, but it is important to remember
that oesophageal atresia is one of the causes
5-10 Can chorioamnionitis cause which need to be excluded after delivery.
complications during the puerperium?
Yes. Chorioamnionitis may cause infection of 5-12 Which patients are at an increased
the genital tract (puerperal sepsis) which, if risk of preterm labour or preterm
not treated correctly, may result in septicaemia, rupture of the membranes?
the need for hysterectomy, and possibly in Both preterm labour and preterm rupture of
maternal death. These complications can membranes are more common in patients who:
usually be prevented by starting a course of
broad spectrum antibiotics (e.g. ampicillin plus 1. Have a past history of preterm labour.
metronidazole), as soon as the diagnosis of 2. Have no antenatal care.
clinical chorioamnionitis is made. 3. Live in poor socio-economic
circumstances.
Bacteria that have colonised the amniotic fluid 4. Smoke, use alcohol or abuse habit-forming
may infect the fetus, and the infant may present drugs.
with signs of infection at, or soon after, birth. 5. Are underweight due to undernutrition.
6. Have coitus in the second half of
5-11 What factors other than chorio- pregnancy, when they are at an increased
amnionitis can lead to preterm labour and risk of preterm labour
preterm rupture of the membranes? 7. Have any of the maternal, fetal or placental
The following maternal, fetal and placental factors listed in 5-11.
factors may be associated with preterm labour
and/or preterm rupture of the membranes: The most important risk factor for preterm
labour is a previous history of preterm delivery.
1. Maternal factors:
• Pyrexia, as the result of an acute
infection other than chorioamnionitis, 5-13 What can be done to decrease the
e.g. acute pyelonephritis or malaria. incidence of these complications?
• Uterine abnormalities, such as 1. Take measures to ensure that all pregnant
congenital uterine malformations women receive antenatal care.
(e.g. septate or bicornuate uterus) and 2. Identify patients with a past history of
uterine myomas (fibroids). preterm labour.
• Incompetence of the internal cervical 3. Give advice about the dangers of smoking,
os (‘cervical incompetence’). alcohol and the use of habit-forming drugs.
4. 120 MATERNAL CARE
4. Advise against coitus during the late second
All patients should be told to immediately
and in the third trimester in pregnancies
report preterm labour or preterm rupture of the
at high risk for preterm labour or preterm
rupture of the membranes. If coitus occurs membranes.
during pregnancy in these patients, the use
of condoms must be recommended as this 5-15 What should you do if a patient
may reduce the risk of chorioamnionitis. threatens to deliver a preterm infant?
5. At 14–16 weeks, insert a McDonald suture
1. Infants born between 34 and 36 weeks can
in patients with a proven incompetent
usually be cared for in a level 1 hospital.
internal cervical os.
2. However, women who deliver between 28
6. Prevent teenage pregnancies.
and 33 weeks, should be referred to a level
7. Improve the socio-economic and
2 or 3 hospital with a neonatal intensive
nutritional status of poor communities.
care unit.
8. Arrange that the workload of women,
3. If the birth of a preterm baby cannot be
who have to do heavy manual labour, is
prevented, it must be remembered that the
decreased when they are pregnant and
best incubator for transporting an infant
that an opportunity to rest during working
is the mother’s uterus. Even if the delivery
hours is allowed.
is inevitable, an attempt to suppress labour
should be made, so that the patient can be
5-14 How should you manage a patient transferred before the infant is born.
at increased risk of preterm labour or 4. The better the condition of the infant on
preterm rupture of the membranes? arrival at the neonatal intensive care unit,
1. Patients at increased risk must have two the better the prognosis.
weekly vaginal examinations from 24
weeks, in order to make an early diagnosis
of preterm cervical effacement and/or DIAGNOSIS OF
dilatation.
2. In all women with cervical effacement or
PRETERM LABOUR AND
dilatation before 34 weeks, the following PRETERM RUPTURE OF
preventive measures can then be taken:
• Bed rest. This can be at home, except
THE MEMBRANES
when the home circumstances are poor,
in which case the patient should be
5-16 How should you distinguish
admitted to hospital.
between Braxton Hicks contractions and
• Sick leave must be arranged for
the contractions of preterm labour?
working patients.
• Coitus must be forbidden. Braxton Hicks contractions:
• Patients must immediately report 1. Are irregular.
if contractions or rupture of the 2. May cause discomfort but are not painful.
membranes occur. 3. Do not increase in duration or frequency.
• Women with preterm labour or preterm 4. Do not cause cervical effacement or
rupture of the membranes must be seen dilatation.
as soon as possible, and the correct
measures taken to prevent the delivery The duration of contractions cannot be used
of a severely preterm infant. as a distinguishing factor, as Braxton Hicks
contractions may last up to 60 seconds.
In contrast, the contractions of preterm or
early labour:
5. PRETERM LABOUR AND PRETERM RUPTURE OF THE MEMBRANES 121
1. Are regular, at least one per ten minutes. 4. If no drainage of liquor is seen, a smear
2. Are painful. should be taken from the posterior
3. Increase in frequency and duration. vaginal fornix with a wooden spatula to
4. Cause effacement and dilatation of the determine the pH and to test for ferning.
cervix. 5. The possibility of cord prolapse can be
excluded or confirmed.
5-17 How should you confirm the 6. It is also important to see whether the
diagnosis of preterm labour? cervix is long and closed, or whether
there is already clear evidence of cervical
Both of the following will be present in a effacement and/or dilatation.
patient of less than 37 weeks gestation: 7. A patient with a profuse vaginal discharge
1. Regular uterine contractions, palpable on or stress incontinence (leaking urine
abdominal examination, of at least one when coughing or laughing) may think
per ten minutes. that she is draining liquor. A speculum
2. A history of rupture of the membranes, or examination will help to confirm or rule
cervical effacement and/or dilatation, on out this possibility.
vaginal examination.
NOTE If the facilities are available, and preterm
rupture of the membranes has been confirmed,
5-18 How can you diagnose preterm an endocervical swab could be taken to culture
rupture of the membranes? for Group B Streptococcus and Gonococcus.
1. A patient of less than 37 weeks gestation
will give a history of sudden drainage 5-20 How should you test the vaginal pH?
of liquor followed by a continual leak
1. The pH of the vagina is acidic but the pH
of smaller amounts, without associated
of liquor is alkaline.
uterine contractions.
2. Red litmus paper is pressed against the
2. A sterile speculum examination will
moist spatula. If the red litmus changes to
confirm the diagnosis of ruptured
blue, then liquor is present in the vagina,
membranes.
indicating that the membranes have
3. A digital vaginal examination must not be
ruptured. If blue litmus is used, it will
done as it is of little value in diagnosing
remain blue with rupture of membranes or
rupture of the membranes and may
change to red if the membranes are intact.
increase the risk of infection.
5-21 How will you test for ferning?
A digital vaginal examination must not be done
1. The vaginal fluid on the wooden spatula is
if there is preterm rupture of the membranes. spread on a microscope slide and allowed
to dry.
5-19 What is the value of a sterile 2. The slide is then examined under the
speculum examination when preterm low power lens of a microscope. An
rupture of the membranes is suspected? unmistakable pattern of a fern leaf will be
observed if the specimen is liquor.
1. The danger of ascending infection is not
increased by this procedure.
2. Observing drainage of liquor from the
cervical os confirms the diagnosis of
ruptured membranes.
3. If no drainage of liquor is observed,
drainage can sometimes be seen if the
patient is asked to cough.
6. 122 MATERNAL CARE
MANAGEMENT OF 7. Antepartum haemorrhage of unknown
cause.
PRETERM LABOUR 8. Cervical dilatation of more than 6 cm.
(However, contractions should be
temporarily suppressed while the patient
5-22 How will you manage a is being transferred to a hospital where
patient in preterm labour? preterm infants can be managed.)
Step 1 9. Severe intra-uterine growth restriction.
Listen to the fetal heart to rule out fetal NOTE Antepartum haemorrhage of unknown
distress and determine the duration of cause may be due to a small abruptio
pregnancy as accurately as possible: placentae. It is, therefore, advisable not
to suppress labour should it occur.
1. If fetal distress is present and the fetus is
assessed to be viable (28 weeks or more),
then the infant must be delivered as soon 5-24 How will you decide that a patient
as possible. is less than 36 weeks pregnant if the
2. If the pregnancy is 34 weeks or more, duration of the pregnancy is unknown?
labour should be allowed to continue. This is done by measuring the symphysis-
3. If the infant is assessed to be 24 weeks fundus height and by doing a complete
or more but less than 34 weeks, other abdominal examination.
contraindications for the suppression
of preterm labour must be excluded. Labour must be suppressed if the estimated
Subsequently the contractions should fetal weight is less than 2000 g or the estimated
be suppressed with a calcium channel gestational age less than 34 weeks. The
blocker, e.g. nifedipine (Adalat), or a beta2 symphysis-fundus height measurement will be
stimulant, e.g. salbutamol (Ventolin). The less than 33 cm.
further management of these patients must
take place in a level 2 or 3 hospital. 5-25 How should you give nifedipine for
4. The administration of steroids to enhance the suppression of preterm labour?
fetal lung maturity prior to transfer should 1. Three nifedipine (Adalat) 10 mg capsules
be discussed with the referral hospital. (total 30 mg) should be taken by mouth.
Step 2 If there are no further contractions and
no continuing cervical dilatation and
Look for treatable causes of preterm labour, effacement, 20 mg should be given eight-
such as urinary tract infection or malaria. hourly.
The management of a patient with preterm 2. If there are still contractions with cervical
labour is summarised in flow diagram 5-1. dilatation and effacement three hours
after the initial dose, a second dose of
5-23 What are the contraindications to 20 mg should be given, followed by eight-
the suppression of preterm labour? hourly doses.
1. Fetal distress. Nifedipine (Adalat) has fewer side effects
2. A pregnancy where the duration is 34 than salbutamol for the mother. Following
weeks or more, or 24 weeks or less. the latest research, nifedipine (Adalat) has
3. Chorioamnionitis. been recommended as the drug of choice in
4. Intra-uterine death. suppressing uterine contractions.
5. Congenital abnormalities incompatible
with life.
6. Pre-eclampsia.
7. PRETERM LABOUR AND PRETERM RUPTURE OF THE MEMBRANES 123
Conservative Preterm
management Labour
No
Yes
28 weeks or more? Fetal distress?
Yes
No
1.Intra-uterine No Yes
Treat infection
resuscitation Gestational age less Urinary tract
and suppress
2.Deliver as soon as than 24 weeks? infection?
labour
possible
No
Yes
Yes
Cervical dilatation Give nifedipine
Deliver
6 cm or less?
No Yes
Yes
Neonatal care Duration of pregnancy
Deliver
available? less than 32 weeks?
No Yes No
Suppress labour Give Do not give
and refer to a indomethacin indomethacin
level 2 or 3
hospital
Flow diagram 5-1: The management of a patient with preterm labour when the duration of pregnancy is less
than 34 weeks
8. 124 MATERNAL CARE
5-26 What are the contraindications to the administration of the drug should be stopped
use of nifedipine in suppressing labour? and preparation made for the delivery of a
preterm infant.
1. Nifedipine (Adalat) cannot be used for the
suppression of preterm labour if patients
have hypertension, or are suffering from any 5-28 What are the contraindications
of the hypertensive disorders of pregnancy. to the use of beta2 stimulants
2. Hypovolaemia or surgical shock due to any in suppressing labour?
reason. 1. Heart valve disease. The use of beta2
3. Any condition that impairs the function of stimulants, such as salbutamol, can endanger
the myocardium. the patient’s life, especially if she has a
narrowed heart valve, e.g. mitral stenosis.
5-27 How should you use salbutamol for 2. A shocked patient.
the suppression of preterm labour? 3. A patient with tachycardia, e.g. as the result
of an acute infection.
1. Start an intravenous infusion of Ringer’s
lactate and give 250 μg (0.5 ml) salbutamol
slowly intravenously, after ensuring that 5-29 What additional action must
there is no contraindication to its use. The you take to suppress labour?
0.5 ml salbutamol is diluted with 9.5 ml Prostaglandin antagonists, e.g. indomethacin
sterile water and given slowly intravenously (Indocid), are prescribed. One indomethacin
over five minutes while the maternal heart 100 mg rectal suppository is administered 12-
rate is carefully monitored for tachycardia. hourly. Two doses are usually sufficient. The
2. The initial dose is followed by a side- total dose should not exceed four doses (i.e. it
infusion of 200 ml saline with 1000 μg shouldn’t be taken for more than 48 hours).
salbutamol given at a rate of 30 ml per
hour (150 μg per hour) until no further The following side effects make indomethacin
contractions occur, or when the maternal potentially dangerous:
pulse rate reaches 120 beats per minute. 1. Gastrointestinal irritation.
If contractions persist, after two hours the 2. Suppression of platelet function.
dose is doubled to 60 ml per hour (300 μg 3. Fluid retention.
per hour) until no further contractions 4. Premature closure of the ductus arteriosus
occur, or when the maternal pulse in the fetus.
rate reaches 120 beats per minute.The 5. Renal failure in a patient with poor renal
administration of the salbutamol infusion function.
is continued until there are no further
Indomethacin is also a useful drug to use if
contractions, effacement, and/or dilatation
there is a contraindication to giving a beta2
of the cervix for at least six hours.
stimulant, e.g. maternal tachycardia due to
3. The patient must be warned that salbutamol
pyrexia. The risk of fetal death due to closure of
causes tachycardia (palpitations).
the ductus arteriosus by indomethacin is much
4. Patients should be monitored with an
greater after 31 weeks. Therefore, indomethacin
ECG monitor while receiving intravenous
should not be used from 32 weeks gestation.
salbutamol. This should ideally occur
within a high-care unit. Successful suppression of preterm labour
with nifedipine (Adalat) or salbutamol
If the contractions are still occurring, and
together with indomethacin is more likely if
there is progressive effacement and dilatation
antibiotics (ampicillin and metronidazole)
of the cervix in spite of an adequate rate of
are given in addition. Possible asymptomatic
administration, alternative measures must
chorioamnionitis will then be treated as well.
be taken to suppress labour. Otherwise,
9. PRETERM LABOUR AND PRETERM RUPTURE OF THE MEMBRANES 125
5-30 How should you manage the 3. The patient must continually be observed
patient further, after labour has for signs of fluid overload, the first sign of
been successfully suppressed? which is the presence of crepitations in the
lungs as a result of pulmonary oedema.
1. If there is a treatable cause, e.g. a urinary
tract infection, then no further suppression
of labour is necessary after the cause has 5-33 If the delivery of a preterm infant
been treated. cannot be prevented, what action
2. If nothing can be done about the cause should you take in order to make
of the preterm labour, e.g. in the case of a the delivery as safe as possible?
multiple pregnancy or polyhydramnios, 1. The mother must be transferred before
nifedipine (Adalat) 20 mg may be given delivery to a hospital where preterm
orally every six hours. infants can be managed.
2. Entonox (50% nitrous oxide and 50%
5-31 What other action can be taken oxygen) or an epidural anaesthetic are the
to improve the fetal outcome? preferred methods of providing analgesia.
3. The membranes should not be ruptured
1. Steroids administered parenterally to the
as they form a better cervical dilator
mother cross the placenta and hasten the
than the small fetal head. If they
onset of fetal lung maturity. Betamethasone
rupture spontaneously, a sterile vaginal
(Celestone-Soluspan) 12 mg (2 ml)
examination must be done to exclude an
intramuscularly is the drug of choice.
umbilical cord prolapse.
2. Two doses of 12 mg each are given
4. A spontaneous vertex delivery, with
24 hours apart. Fetal lung maturity is
an episiotomy if necessary, is the best
usually, but not always, achieved 24 hours
method of delivery. A well-controlled
after the second dose. Suppression of
delivery of the fetal head reduces the risk
labour for 48 hours in order to give
of intracranial haemorrhage. There is no
betamethasone is, therefore, of value.
evidence that the routine use of forceps has
3. If the infant is not delivered and there is
any advantage for the preterm infant.
still a risk of preterm delivery, a single dose
5. Before the delivery, you must make sure
of 12 mg can be given after a week. The
that the equipment you need for the
dose should not be repeated weekly until a
resuscitation and management of the
gestational age of 33 weeks is reached.
preterm infant is available and in working
NOTE : Fetuses that are exposed to repeated doses
order.
of steroids in pregnancy are born with a smaller
head circumference and length. As the long-term
neurological outcome is uncertain, the maximum MANAGEMENT OF
dose described here should not be exceeded.
PRETERM RUPTURE OF
5-32 What are the dangers of using THE MEMBRANES
steroids to promote fetal lung maturity?
1. Steroids must not be given if a clinically
5-34 How should you manage preterm
detectable infection is the cause of the
rupture of the membranes?
preterm labour, because they may make
the infection worse. There are two possible ways of managing
2. Steroids cause fluid retention. Consequently, preterm rupture of the membranes:
the amount of intravenous fluid which is 1. Labour can be induced.
used to administer the salbutamol must be 2. The pregnancy can be allowed to continue.
restricted.
10. 126 MATERNAL CARE
The management of a patient with preterm movements. Antenatal fetal heart rate
rupture of the membranes is summarised in monitoring is of great value.
flow diagram 5-2. 2. Determine the duration of the pregnancy
as accurately as possible. Remember, with
5-35 How should you decide which preterm rupture of the membranes, both
method of management to use? clinical and ultrasound examinations tend
to underestimate the duration of pregnancy.
The danger of prematurity if the fetus is 3. Look for signs of clinical chorioamnionitis.
delivered must be weighed against the risk of
infection in both the mother and the fetus if If the history and clinical examination indicate
the pregnancy is allowed to continue. a pregnancy of less than 34 weeks duration,
an ultrasound examination is of value in
5-36 What is the reason for allowing determining fetal size and possible gross
the pregnancy to continue with congenital abnormalities.
preterm rupture of the membranes?
5-39 What are the indications for
To provide time for the fetal lungs to mature induction of labour when preterm rupture
and, thereby, to reduce the danger of hyaline of the membranes has occurred?
membrane disease after delivery.
1. An HIV-positive patient.
2. A duration of pregnancy of 34 weeks or
Prematurity remains the commonest cause of more.
neonatal death resulting from preterm rupture 3. A duration of pregnancy less than 26 weeks.
of the membranes. 4. Intra-uterine death or severe fetal
congenital abnormalities.
5-37 Which patients with preterm 5. Signs of clinical chorioamnionitis.
rupture of the membranes are at an 6. Maternal illness such as pre-eclampsia or
increased risk of chorioamnionitis? diabetes mellitus.
7. Severe intra-uterine growth restriction.
Patients with preterm rupture of the 8. Antepartum haemorrhage of unknown
membranes plus one or more of the following cause.
factors are at a particularly high risk of
chorioamnionitis: 5-40 What method of induction
1. HIV-positive patients with immune should you use?
suppression, either: The method of choice is to stimulate uterine
• A CD4 count of less than 350 cells/mm3. contractions with oxytocin. If there are
• An AIDS-defining infection that contraindications to stimulating labour or to
indicates clinical immune suppression. a vaginal delivery, then a Caesarean section
2. Rupture of the membranes during or is done.
following coitus.
3. A digital vaginal examination following
5-41 What should the daily care of a patient
rupture of the membranes.
include if pregnancy is allowed to continue?
4. No antenatal care.
1. The patient must be kept on bed rest, being
5-38 What should you do once preterm allowed up to the toilet. She must not sit in
rupture of the membranes has occurred? a bath, but should use a shower.
2. Digital vaginal examinations must not be
1. Check whether the fetus is still alive, and done.
exclude fetal distress by assessing fetal 3. The condition of the fetus must be
monitored daily, preferably with a
11. PRETERM LABOUR AND PRETERM RUPTURE OF THE MEMBRANES 127
Conservative Prelabour rupture
management of membranes
No
Yes No Sterile
28 weeks or more? Fetal
speculum
distress?
examination
Yes
1.Intra-uterine No
resuscitation Discharge Liquor in
2.Deliver as soon as vagina?
possible
Yes
Yes
Prolapsed
cord?
No
Yes Duration of pregnancy less
Oxytocin to than 26 weeks, or 34 or
induce labour more weeks?
No
No
Yes Signs of clinical Conservative
chorioamnionitis? management
Flow diagram 5-2: The management of a patient with preterm prelabour rupture of the membranes
12. 128 MATERNAL CARE
cardiotocograph. If this is not available, fetal develop contractions before 24 hours have
movements must be counted and recorded. passed after giving steroids, and there are no
4. Observations for signs of clinical clinical signs of chorioamnionitis or any other
chorioamnionitis must be done: contraindications to the suppression of preterm
labour, the labour must be suppressed with
• The maternal pulse rate and
nifedipine (Adalat) or salbutamol (Ventolin).
temperature and the fetal heart rate An attempt is thus made to expose the fetal
must be checked four-hourly. lungs to steroids for at least 24 hours.
• An abdominal examination is done
twice a day to check for uterine
5-43 Which physical signs will be
tenderness.
present if a patient develops severe
• At the same time it is noted whether or
infection (septic shock) and what
not the liquor is offensive.
will the initial management be?
1. The signs of clinical chorioamnionitis
The first digital vaginal examination in a patient already mentioned will be present. In
with preterm rupture of the membranes is done addition, there will be a drop in the blood
only when she is in established labour. pressure and cold clammy extremities, if
severe infection (septic shock) develops.
5-42 How long should you allow 2. The patient must be actively resuscitated
the pregnancy to continue? and treated with ampicillin, metronidazole
(Flagyl) and gentamicin. The patient must
1. If complications, such as chorioamnionitis then be referred to a level 2 or 3 hospital.
and fetal distress, do not develop, the
pregnancy is allowed to continue until
5-44 What advice should you
the patient goes into labour. However, if
give to a woman who has
the pregnancy reaches 34 weeks duration
delivered a preterm infant?
and the patient is still draining liquor, an
oxytocin induction is done. 1. She should be seen before her next
2. A patient who has stopped draining liquor pregnancy to be assessed for possible
completely and where liquor is present causes, e.g. cervical incompetence.
on abdominal examination, with no signs 2. She must book early in any future
of chorioamnionitis, may be allowed pregnancy.
to continue her pregnancy until the
spontaneous onset of labour. The patient
may be allowed home if no liquor has PRELABOUR RUPTURE
drained for two days. However, she is not
allowed to sit in a bath or to have coitus.
OF THE MEMBRANES
The patient must be followed up weekly at
a high-risk clinic.
5-45 How should you manage a patient
NOTE The administration of steroids will promote
with prelabour rupture of the membranes?
fetal lung maturity if patients with preterm 1. If a patient has prelabour ruptured
rupture of the membranes are managed membranes and there are signs of
conservatively. Betamethasone (Celestone chorioamnionitis, then labour should be
Soluspan) 12 mg (2 ml) is given intramuscularly.
induced without delay.
The dose is repeated after 24 hours. Because
steroids may increase the risk of infection, 2. HIV-positive patients should be started on
ampicillin and metronidazole (Flagyl) must a course of antibiotics and labour should
also be prescribed, as in the case where be induced:
preterm labour is being suppressed. If a patient
who is being managed in this way should
13. PRETERM LABOUR AND PRETERM RUPTURE OF THE MEMBRANES 129
• The longer the interval between rupture 3. Why could chorioamnionitis still be
of the membranes and delivery, the the cause of her preterm labour?
greater the risk of mother-to-child
Because chorioamnionitis is often
transmission of HIV.
asymptomatic.
• The patient has a higher risk of
chorioamnionitis.
3. However, if the patient is at low risk of 4. Would you allow labour to continue
chorioamnionitis and both fetal and or would you suppress labour?
maternal conditions are good, you can Labour should be suppressed because the
wait for 24 hours after the membranes pregnancy is of less than 34 weeks duration,
have ruptured before inducing labour. the fetus is viable, and there are no signs of
About 80% of patients will go into labour clinical chorioamnionitis or fetal distress.
spontaneously within this period. A digital
vaginal examination should not be done 5. How should labour be suppressed?
until the patient is in labour.
Labour must be suppressed using nifedipine
NOTE In busy hospitals with a high bed (Adalat) or salbutamol (Ventolin).
occupancy rate, patients with prelabour rupture
of the membranes can have their labour induced 6. Which other drugs would
with oxytocin after the diagnosis is confirmed.
increase the chance of successful
Induction of labour in these circumstances
does not result in a higher Caesarean section suppression of preterm labour?
rate but reduces hospital stay by 24 hours. Antibiotics, such as ampicillin and
metronidazole (Flagyl), increase the likelihood
of successful suppression of preterm labour
CASE STUDY 1 if the labour is caused by asymptomatic
chorioamnionitis.
A patient, 32 weeks pregnant, presents with
regular painful uterine contractions. She 7. Must indomethicin (Indocid) also
is apyrexial and appears clinically well. On be given?
vaginal examination, the cervix is 4 cm dilated.
No, as the patient is already 32 weeks
The fetal heart rate is 138 beats per minute
pregnant. The risk of closing the ductus
with no decelerations.
arteriosus and causing intra-uterine deaths
increases from 32 weeks.
1. Is the patient in true or false labour?
Give the reasons for your diagnosis.
8. Which drugs can be used to hasten
She is in true labour because she is getting fetal lung maturity, and would you give
regular painful contractions and her cervix is one of these drugs to this patient?
4 cm dilated.
Steroids, such as betamethasone, can be given
to the patient to hasten lung maturity in the
2. What signs exclude a diagnosis fetus. As this patient’s pregnancy is less than
of clinical chorioamnionitis? 34 weeks and there are no signs of clinical
The patient is apyrexial, clinically well and has chorioamnionitis, steroids must be given.
a normal fetal heart rate.
14. 130 MATERNAL CARE
CASE STUDY 2 of rupture can be allowed before inducing
labour. Most patients will go into labour
spontaneously during this period.
A patient, who is 36 weeks pregnant, reports
that she has been draining liquor since earlier
that day. The patient appears well, with normal 6. Should you prescribe antibiotics?
observations, no uterine contractions and the Give your reasons.
fetal heart rate is normal. There is no indication for giving
antibiotics as there are no signs of clinical
1. Would you diagnose rupture chorioamnionitis. However, a careful watch
of the membranes on the history must be kept for early signs of maternal
given by the patient? infection or fetal tachycardia.
No, other causes of fluid draining from the
vagina may cause confusion, e.g. a vaginitis or
stress incontinence. CASE STUDY 3
2. How would you confirm An unbooked patient presents with a five-
rupture of the membranes? day history of ruptured membranes. She is
pyrexial with lower abdominal tenderness and
A sterile speculum examination should be is draining offensive liquor. She is uncertain of
done. If there is no clear evidence of liquor her dates but abdominal examination suggests
draining, the vaginal pH using litmus paper that she is at term. Treatment has been started
and microscopy for ferning can be used to with oral ampicillin.
identify liquor.
1. What signs of clinical chorioamnionitis
3. Why should you not perform a digital does the patient have?
vaginal examination to assess whether
the cervix is dilated or effaced? She is pyrexial, with lower abdominal
tenderness and she has offensive liquor.
A digital vaginal examination is contraindicated
in the presence of rupture of the membranes if 2. Would you induce labour in this
the patient is not already in labour, because of patient? Give your reasons.
the risk of introducing infection.
Yes, because there is danger of spreading
4. Is this patient at high risk of having infection in both the mother and fetus if the
or developing chorioamnionitis? infant is not delivered. The patient is in grave
danger of developing septic shock. Labour
Yes. The preterm prelabour rupture of should be induced with oxytocin, if there
the membranes may have been caused by is no indication for an immediate delivery,
chorioamnionitis. In addition, all patients with e.g. fetal distress. With signs of septic shock,
ruptured membranes are at an increased risk the patient must be actively resuscitated and
of developing chorioamnionitis. treated with broad-spectrum antibiotics,
followed by delivery of the fetus. The earliest
5. Should you induce labour? sign of septic shock will be a fall in the blood
Give your reasons. pressure, followed by the patient developing
cold, clammy extremities.
Yes. As she is more than 34 weeks pregnant,
one should induce labour. As the patient does
not fall into a high-risk group for infection,
a waiting period of 24 hours from the time
15. PRETERM LABOUR AND PRETERM RUPTURE OF THE MEMBRANES 131
3. Should you continue to treat the patient 4. Why is the infant at increased risk
with oral ampicillin? Give your reasons. for neonatal complications?
She should be treated with appropriate broad- The chorioamnionitis has already spread to the
spectrum antibiotics, given in adequate liquor as this is offensive. Therefore, the fetus
dosages until her pyrexia has subsided. As it may also be infected and may present with
is not clear how long the infection has been congenital pneumonia or septicaemia at birth.
present, gentamicin must be added to the
ampicillin and metronidazole (Flagyl) until
the patient has been apyrexial for 24 hours.
The gentamicin and ampicillin must initially
be given intravenously and the metronidazole
as a rectal suppository.