CO (ppm)
20 and
above
20
19
18
17
16
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
% FCOHB
Baby’s CO reading
In pregnancy your
metabolism is increased,
which can result in a low
CO reading – however
this does not mean you
or your baby are at less
risk.
If you are a smoker,
other factors that
can affect the reading
include:
• The time of day the
test is performed
(morning readings are
lower than
later in the day).
• How much you have
smoked in the last few
hours before the test.
• The smoking of
cannabis or shisha.
CO Guide Chart
Your CO reading
What can affect
the result?
6.26
5.95
5.63
5.32
5.00
4.69
4.38
4.07
3.76
3.44
3.13
2.82
2.50
2.19
1.88
1.56
1.20
0.94
0.63
0.31
Heavy
Smoker
NonSmoker
For free, friendly advice and support for you and your family contact:
Dudley Stop Smoking and Pregnancy Service
Telephone 0800 0850 652 text ‘CAN’ to 80800
or go online at www.dudleystopsmoking.co.uk
You, your baby and
Carbon Monoxide.
What is Carbon Monoxide (CO)?
Carbon Monoxide is a toxic gas which you cannot see,
taste or smell. It is released from tobacco smoke,
exhaust fumes and faulty gas appliances.
The effects of
Carbon Monoxide
Why test for
Carbon Monoxide?
• It deprives your muscles, brain
and body tissues of oxygen.
• It damages your placenta.
• It restricts the oxygen supply
to your baby.
• It can lead to poor growth,
premature birth and still birth.
Doing a simple breath test is a
quick and efficient way of letting
you know if you and your baby are
at risk.
As part of your routine antenatal
care you will receive a Carbon
Monoxide test by your midwife.
The good news about
stopping smoking:
And you will also have:
• Your baby will feel the benefits
straight away.
• You will be free from Carbon
Monoxide in less than 24 hours.
• You will reduce the risk of
complications such as premature
birth, still birth, your baby being
born underweight and cot death.
• More money to spend on you
and your baby.
• More time to spend with your
family.
• Reduced stress and anxiety
levels.
• Better health in the future.
How your body
passes carbon
monoxide to
your baby…
CO in smoke enters your
lungs and is absorbed
into your blood stream.
Within a few seconds,
CO then enters your
baby’s bloodstream via
your placenta, damaging
the placenta’s delicate
tissues.
Your baby’s blood
cells then absorb
twice as much
CO as you. This
means there is less
oxygen available to
help make your
baby grow.
Your baby is deprived
of oxygen for 20
minutes each time
you smoke.
Your baby is exposed to twice as much Carbon Monoxide as you every time you smoke.
The earlier you stop smoking in pregnancy the better. But it is never too late to stop!