A1 Life care
Guidance AA1.26 Antenatal ultrasound scans
Teaching notes Further information
You could start by prompting students to describe Women might be offered a scan at any of the
the purpose and procedures associated with following times:
ultrasound scans. They are likely to be familiar with About 6–8 weeks: to confirm/date the pregnancy;
these scans from a multitude of TV dramas. to see if the pregnancy is ectopic (implanted in the
The textbook provides information about how Fallopian tubes, not the uterus); to check the fetus
ultrasound is used to detect and monitor the fetus is alive by looking for the baby’s heartbeat.
inside the mother’s womb. The activity sheet asks About 10–14 weeks: to confirm/date the
questions about the scans in the Textbook. pregnancy; to check for twins or more; alongside a
nuchal scan, which looks specifically at the pad of
Answers to questions skin at the back of the baby’s neck, this can help
1 Gel is rubbed onto the mother’s abdomen assess the risk of the baby having Down’s
because it helps the sound waves to travel from syndrome or other chromosomal conditions.
the transducer in the scanner into the skin, and About 20–23 weeks: to check for spina bifida and
the echoes to travel back out to the microphone other possible abnormalities; to look in detail at
in the scanner. the major organs and the skeleton; to check the
2 Scans are often done at around 12 weeks and health of the placenta; and to check the rate of the
20 weeks. baby’s growth.
Later scans: to monitor the growth of the baby; to
3 a They each have their own.
check the position of the placenta; to check the
b Individual sketches baby’s position.
c The fetus is smaller at 8 weeks, and it may
A website showing ultrasound images is at
not be in such a good position for the scan to www.ob-ultrasound.net/frames.htm
show these features.
d Check scales.
e No, they are fuzzy images which are difficult
to interpret to the untrained eye.
4 Amniotic fluid
5 About 12 cm
6 By 20 weeks all the internal organs have started
7 Down’s syndrome, spina bifida
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