Fetal Movements

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Fetal Movements
All
Earliest recorded fetal movement
Ultrasound
Movie of Fetal Movements
To leave programme
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In this programme you should have learned that
you are completely formed 8 weeks after
conception. The question then arises about
whether or not you were able to function at that
time?.
When a woman is pregnant, one of the first
questions people ask is Have you felt the baby
move yet?. If it is the womans first pregnancy,
then she will not respond with yes until around
week 19. With subsequent pregnancies she will be
able to feel the movements around week 14. This
is because she knows what to expect for the
movements and can feel them earlier.
(I have never been pregnant so I cannot really
give personal experience on this but apparently
the women can feel butterfly movements or
faint scratching taking place which gets
greater in intensity as the pregnancy progresses.
The women can recognise the initial development
of these movements earlier with subsequent
pregnancies.)
But this still leaves the question Were you
able to move between weeks 8 and 14 after
conception or did you just lie there in utero not
moving?
People have tried to answer that question.
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Here is an experiment from the 1920s that could
not be performed in these days. The pictures
show an aborted, human embryo lying in a dish of
saline with a black background. The embryo is
only 6 weeks old (conceptual age) - look at the
features.
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Somebody is trying to get the embryo to move by
stroking its cheek with a fine hair. This is a
good place to try to elicit a reflex because it
would stimulate the suckling reflex - the first
reflex to develop.
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The response of the embryo is to move its arms up
and down slightly and to tilt its pelvis. On the
basis of this evidence, you might say that it can
move. But then some people said No, the embryo
does not move at this age. This is simply a
survival mechanism as this embryo knows that it
is dying. And so for a long time people did not
know whether or not embryos and fetuses moved in
utero at this age.
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Left arm
Left knee
Umbilical cord
head
Right foot
Left foot
But then along came ultrasound and we were able
to see inside the uterus. Here you can see a
woman undergoing an ultrasound scan. She is lying
on her back with her head to the right, feet to
the left and you can identify the various parts
of the fetus in her uterus.
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Left arm
Left knee
Umbilical cord
head
Right foot
Left foot
The ultrasound transducer provides us with a 1 cm
wide window to look inside the uterus. In this
picture you can see an outline of the babys head
and the image of the cleft between the two
hemispheres.
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Left arm
Left knee
Umbilical cord
head
Right foot
Left foot
One thing that you must notice is the cramped
conditions of this 8-month old fetus. This
cramped position of the fetus and the lack of
space in which to move is the image people have
of fetuses in utero. You are just about to see
that fetuses have much more room in which to move
earlier in pregnancy!
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This is a typical ultrasound picture of a 12 week
old fetus. He/she is lying on their back in a
large pool of amniotic fluid. Although you can
see the lower limb, the foot is not visible.
This does not mean that this fetus does not have
a foot, it simply means that it is not in the 1cm
slice window that is available. The face and
limbs are also not visible for the same reason.
Placenta
Umbilical cord
Head
Lower limb
Body
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We were interested in determining if the fetus
moved between 8 and 14 weeks after conception and
also, if the fetus did move, why the mother could
not feel the movements. Therefore we took a
series of women who were each around 12 weeks
pregnant and monitored the fetal movements using
ultrasound.
We asked the mothers to lie quietly for 5 mins
before we started recording and they often became
very drowsy and fell asleep. We woke them up
gently for the experiment and asked them to
indicate whenever they felt a fetal movement.
None of the mothers felt any movement throughout
the recording period! We concluded that as the
uterus is insensitive to touch and stretch, the
fetal movements have to be so fierce that they
affect the anterior abdominal wall - which is
where the mothers can feel the movements.
In the following movie, watch out for - the
large amount of space that these fetuses have at
12 weeks after conception - the fetuses standing
on their heads and stretching out their legs! -
fetuses sucking their thumbs and jerking
movements of the fetuses - the fetal heart beat -
the one fetus that is only 6 weeks after
conception. It is there to highlight the large
amount of space available for the fetus to move
at this time.
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Fetal movements at 12 weeks of age after
conception.
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Now that you have seen how much young fetuses
move, let me ask you a question When your
parents first took you home and changed your
diaper for the first time, they laid you out on a
towel on your back - and you just lay there
unable to move. Why were you not able to move?.
You were no longer floating in fluid and gravity
had reared its ugly head and said Hello! You
did not have the strength to move. Three months
later when you could just about sit up by
yourself or just about roll over onto your face,
your parents were delighted as these are
milestones of development after birth - but, as
you have seen, you could move much more than this
long before you were born! Movements are not just
restricted to the limbs. You are able to swallow
and you practice chest wall movements in
preparation for breathing. I wonder what it is
that you swallow?
Perhaps the biggest thing to realise about the
whole of embryology is that you are completely
formed 8 weeks after conception. Not only are you
formed but you are also fully functioning. When
do most women realise that they are pregnant?