B3: 10 Pregnancy HO1
GP Drug & Alcohol
Supplement No.14
August 2001
Drugs in Pregnancy
Dr Vicki Chase
Helen Astolfi
Dr Sally McKenna
Introduction
Many legal and illegal drugs used during
pregnancy may interfere with the
development of the foetus, and or result in
complications during or after childbirth. In
addition, drugs used by breast-feeding
mothers may pass through the breast milk to
the child.
The 1998 National Drug Strategy Survey1
identified the following:
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26% of pregnant women smoke
tobacco
73% of pregnant women drink alcohol,
17% drinking more than 3 standard
drinks per day
17% of pregnant women use cannabis.
1.3% of pregnant women use
intravenous drugs.
Drug use may increase isolation through
fear of professional support and as a result
many women do not receive adequate
antenatal care.
Drug use that continues after the child is
born may seriously interfere with effective
parenting and put the newborn child at risk.
The Child Death Review 1997-98 showed a
positive correlation between neonatal deaths
and parental substance abuse.
Harm Associated with Antenatal
Substance Misuse
The use of drugs during pregnancy causes
harm to the foetus, the neonate, the mother
and the family. Harm to the foetus and
neonate includes:
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premature delivery
increased risk of low birth weight
increased prenatal mortality
higher incidence of congenital
abnormalities
neonatal toxicity/withdrawal
failure to thrive and developmental delay
higher incidence of Sudden Infant Death
Syndrome (4-5 fold)
substances can also affect the health of
the mother and therefore her ability to
adequately nourish the child.
Risks associated with drug use such as HIV,
Hepatitis B, Hepatitis C, malnutrition,
anaemia, sexually transmitted diseases and
respiratory depression can all affect the
unborn child and the mother.
Drug use during pregnancy may lead to
relationship problems with the partner,
family and friends resulting in reduced
parental supports.
Withdrawal symptoms in babies born
addicted to substances can make them
difficult to manage and can reduce motherchild bonding.
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GP Drug & Alcohol Supplement No. 14
match the patient to the appropriate
treatment. It will also highlight situations
where there are concerns surrounding child
safety.
Treatment Aims
Treatment aims for substance-using
pregnant women are the same as for all
women. These include:
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The assessment should determine:
the provision of comprehensive
antenatal and postnatal care, and,
minimisation of complications.
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There are often many barriers to achieving
these aims, however, pregnancy can be a
powerful incentive for some women to
change their alcohol and or drug use.
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For other women it can prove difficult.
Sometimes, pregnant women who abuse
substances are not fully aware of the foetal
harm exposure to drugs and or alcohol may
cause.
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A careful alcohol and other drug
assessment provides the opportunity for
informing and educating the woman about
the adverse effects substance use has on
the developing foetus. It is also an
opportunity to explore the patient’s
readiness to change (see Supplement No.6
Motivational Interviewing).
The goal of intervention should be harm
minimisation through coordinated care
provided by a multi-disciplinary team.
Attempts should be made to facilitate all
women accessing available services.
Antenatal care should be tailored to the
specific needs of the substance-using
mother.
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Drug and Alcohol effects during
pregnancy
The effects of alcohol exposure during
pregnancy are related to the amount of
alcohol ingested and the general health of
the woman. The effects occur along a
continuum from a small decrease in
cognitive functioning to Foetal Alcohol
Syndrome (FAS) as the most severe3. FAS
includes the following features:
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Motivational interviewing techniques can be
used to shift the mother towards decreasing
drug use and set realistic and achievable
goals. However, if drug use continues, safer
drug using practices should be encouraged.
Assessment
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drug use (type, amount, pattern of use,
dependency, current and previous
treatments)
drug related problems (health, lifestyle,
relationship and legal)
stage of change regarding reducing or
stopping drug use
knowledge regarding potential harm to
foetus
access and use of antenatal care
mental health
relationship of mother to unborn child
partners drug use and willingness to be
involved in child rearing
other socioeconomic factors such as
accommodation, financial situation and
social support.
Alcohol
Antenatal care has been shown to be a
crucial factor in determining pregnancy
outcome. It can reduce the risks of pre-term
and small for gestational age births, even in
the presence of other risk factors2.
The provision of regular follow-up after
delivery is crucial in maintaining ongoing
support.
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growth retardation
CNS abnormalities
facial abnormalities.
The time of greatest sensitivity of the foetal
brain is the third trimester, if the patient is
successful in achieving abstinence prior to
then, the foetal brain may escape damage.
To date, epidemiological studies have
failed to demonstrate a threshold dose for
risk, thus total abstinence from alcohol is
the safest advice to give a pregnant
woman.
A thorough alcohol and other drug
assessment will provide the General
Practitioner with sufficient information to
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GP Drug & Alcohol Supplement No. 14
Tobacco
There is no safe level of tobacco use,
particularly during pregnancy.
Nicotine has been shown to impair
placental function through its effects on
placental vessels thus interfering with
nutrient uptake and the ongoing health of
the placenta.
Foetal growth is reduced. The reduction in
birth weight is in direct proportion to the
number of cigarettes smoked, averaging
around 200 grams.
Nicotine increases the foetus’ heart rate and
carbon monoxide impairs the conveyance of
oxygen.
There is an increased risk of ectopic
pregnancy, miscarriage, placental abruption
and premature labour associated with
tobacco use during pregnancy4. Prenatal
mortality increases by approximately 35%5.
Tobacco cessation at any time during the
pregnancy will be beneficial to the health of
the newborn.
Cannabis
It is difficult to determine the specific effects
of cannabis on the foetus because it is
usually ingested in combination with other
substances, most commonly with alcohol
and tobacco.
We do know that tetrahydrocannabinol
(THC) the active constituent of cannabis
crosses the placenta and is stored in fat.
THC accumulates in the fatty tissues of the
brain, possibly affecting the child before and
after birth.
The complications associated with cannabis
include reduced birth weight and an
increase in premature labour. In addition,
neonates appear to have tremors, increased
startle reflex, poor self-quieting and
disordered sleep cycles.
Benzodiazepines
Benzodiazepines may cause Neonatal
Abstinence Syndrome. Pregnant women
who are dependent on benzodiazepines
should not cease their use abruptly. A slow
benzodiazepine detoxification is
recommended with close medical
supervision (see Supplement No.9
August 2001
Benzodiazepine Dependence &
Withdrawal).
Psychostimulants
Research is again difficult in this area
because of the confounding effects of poly
drug use and poor maternal nutritional
status. Amphetamine and cocaine use
during pregnancy is however consistently
associated with increased incidence of
miscarriage, premature labour, placental
abruption and foetal distress6.
Opioid dependent pregnant women
Opiate use in pregnancy endangers the
health of both the mother and her foetus.
Continual fluctuations in the blood opiate
levels, exposure to a diverse range of
drugs, and infections that can be related to
injecting drug use are some of the primary
concerns. Lifestyle factors associated with
opiate
dependency
can
also
be
problematic10.
Obstetric complications related to opiate
use include:
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intrauterine growth retardation
intrauterine infection
pre-eclampsia
antepartum & postpartum hemorrhage
miscarriage
premature labour
risk of physical dependence in the foetus
and subsequent withdrawal in the
neonate.
Management options for the opiate
dependent pregnant woman
Opiate dependant pregnant women who
wish to be treated with methadone do have
priority access to a methadone maintenance
program.
Detoxification
The foetus is very sensitive to changing
states of intoxication and withdrawal.
Detoxification can induce foetal distress,
miscarriage or premature labour. If
attempted it should occur between the 14th
and 32nd weeks under close medical
supervision.
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GP Drug & Alcohol Supplement No. 14
Methadone Maintenance
It has been shown that women in
maintenance programs have longer
pregnancies with fewer obstetric
complications. This includes infants who are
larger for their gestational age than similar
populations not in treatment9. If a pregnant
woman is assessed as suitable for
methadone maintenance therapy she should
be stabilised on a maintenance program as
soon as possible.
Methadone maintenance reduces the
possibility of foetal exposure to unknown
drugs and contaminants. It also eliminates
the fluctuating heroin blood levels
associated with illicit opiate use, which can
stress the foetus.
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neonate is managed in the Special Care
Nursery.
Morphine is the medication of choice in the
management of narcotic dependent infants.
Phenobarbitone is the drug of choice in
withdrawal from non-opiate drugs of
addiction and when abstinence symptoms
include convulsions.
Once stabilised the neonate may be
discharged home on a reducing regime of
the prescribed medication. The Neonatal
Abstinence Working Group (November
2000), state that clear protocols in at risk
assessment, dispensing procedures,
parents’ instructions and coordinated follow
up should be established to support this
approach.
The general principle of treatment is to
achieve stability with the lowest methadone
dose possible. However, if a high dose is
required to enable the woman to cease illicit
opioid use then this should be provided.
The neonate and mother are assessed on a
weekly basis and the prescribed medication
is reduced as tolerated. Reductions should
not exceed 10% of the total dose. The
withdrawal process may take months and
often there will be times when the dose
plateaus for a period. The aim of a slow
reduction is to maximise the mother-baby
relationship and minimise distress7,11.
Neonatal Abstinence Syndrome
Drug use and breast-feeding
Narcotic and non-narcotic drugs of
dependence can cause a withdrawal
syndrome in neonates. The onset and the
severity of neonatal abstinence syndrome
depend on the following:
When a mother is using drugs the
advantages of breast-feeding need to be
weighed up against the disadvantages of
exposing the neonate to the substance
present in the breast milk. The
disadvantages will vary depending on the
type and dosage of the drug used.
Involvement in a maintenance program
facilitates the provision of antenatal care,
parenting education and support.
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type and dosage of drug used
frequency of use and timing of last dose
maturity of neonate and its ability to
metabolise and excrete the drug.
The physical signs of neonatal abstinence
syndrome are characterised by:
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central nervous system irritability
respiratory distress
autonomic symptoms, and,
gastrointestinal dysfunction.
Infants born to methadone maintained
women generally experience some form of
withdrawal usually within 72 hours of birth.
4 hourly scoring, using a neonatal
withdrawal-scoring chart monitors the
severity of neonatal abstinence syndrome.
When scoring reaches a certain point the
Methadone
Women on methadone should be
encouraged to breast-feed. However,
exceptions to this are when a woman is HIV
positive or when a woman who is hepatitis C
positive has cracked or bleeding nipples.
Women taking high doses of methadone
should wean their infants slowly over a
number of weeks to avoid withdrawal in the
infant.
Alcohol
Drinking alcohol whilst breast-feeding is not
recommended as the level of alcohol in the
breast-milk will be equal to the blood alcohol
level. If a women chooses not to cease
drinking during lactation it is recommended
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GP Drug & Alcohol Supplement No. 14
they drink at low risk levels and not within 24 hours of breast-feeding5.
Tobacco
Tobacco use reduces the supply of breast
milk and nicotine is found in breast milk.
Tobacco use should be avoided around
infants, during and prior to feeding5.
Benzodiazepines
Women who are using benzodiazepines
above the therapeutic dose should not
breast-feed. The peak plasma period for
benzodiazepines is within one to two hours
of consumption, therefore, breast-feeding
should be avoided during this period. The
neonate should be closely monitored and if
there are any signs of sedation breastfeeding should be ceased8.
Central Coast Health Support
Services
August 2001
the General Practitioner Local Consultancy
Service during business hours on
0413 276 177. Staff Specialist Obstetricians
are available to consult with GPs regarding
their patients who have drug and alcohol
problems.
The Drug and Alcohol Clinical Advisory
Service is for the exclusive use of local
General Practitioners via Alcohol and Drug
Advisory Service (ADIS) in your state on:
WA:
(08) 9442 5000
1800 653 203
TAS:
(03) 6222 7511
1800 811 994
QLD: (07) 3236 2414
1800 177 833
VIC:
13 15 70
(03) 9416 1818
1800 136 385
NT:
(08) 8981 8030
1800 629 683
Antenatal Assessment
General practitioner and antenatal clinic
‘shared care’ is available for all pregnant
women, and is strongly recommended for
those in whom antenatal substance misuse
is identified.
The booking in clerk at either Gosford or
Wyong can be contacted to arrange an
appointment. Ideally assessment should
occur as early in the pregnancy as possible.
Referral to the community midwives
program can also be arranged through the
antenatal clinics.
ACT: (02) 6205 4545
NSW: (02) 9361 8000
1800 422 599
SA:
1300 131 340
All other enquiries can be made by
contacting the Alcohol and Other Drugs
Service on 02 43 202 637.
Specialist Support
GPs requiring clinical information, support or
specialist consultation are able to contact
REFERENCES
1.
Adhikari, P. & Summeril, A. 2000. 1998 National Drug Strategy Household Survey: Detailed findings AIHW cat. No. PHE 27.
Canberra: AIHW ( Drug Statistics Series No. 6).
2.
Jansson, L.M. et al (1996) ‘Pregnancy and Addiction a Comprehensive Care Model’. Journal Substance Abuse Treatment , 13
(4), 321-329.
3.
Day N.L. & Richardson, G.A. Comparative teratogenicity of alcohol and other drugs. Alcohol Health and Research World, 18 (1),
1994, 42-48
4.
Winstanly M., Woodward S., & Walker N. Tobacco in Australia: Facts and Issues (2nd ed.). Victorian Smoking and Health
Programme, Melbourne, 1995.
5.
Novak, H., et al (1997) “Nursing Care of Drug and Alcohol Problems”. Drug and Alcohol Department, Central Sydney Area
Health Service.
6.
Wickes W. Amphetamines and Other Psychostimulants: A Guide to the Management of Users. Australian Government
Publishing Service, Canberra, 1992.
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July 2001
7.
NSW Health Department 2000. Report of the Neo Natal Abstinence Working Group NSW Pregnancy and Newborn Services
Network.
8.
Brady, J., et al. (1994). The Implications of Prenatal Exposure to Alcohol and Other Drugs. The Education Development Centre,
Inc.
9.
Gillogley., K.M., Evans, A.T., Hansen, R. L. (1990). ‘The perinatal impact of cocaine, amphetamine, and opiate use detected by
universal intrapartum screening’. American Journal Obstetrics & Gynecology, 163 (5pt 1), 1535-1542.
10. Ward., J., Mattick., R., and Hall., W. (1992). “Key Issues in Methadone Maintenance Treatment”. University of NSW press,
Sydney.
11. Woods., J.R. Jr. (1996) “Adverse Consequences of Prenatal Illicit Drug Exposure”. Obstetric. Gynecology v8 n6 403-11.
Central Coast Health