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What is an ultrasound?

Ultrasounds have become the norm for all pregnant women.
In early pregnancy, the ultrasound is used to check everything is in order with the pregnancy such as confirming that the fertilised egg has implanted in the uterus (as opposed to a life threatening ectopic pregnancy where the fertilised egg has implanted outside of the uterus) and to confirm the fetal heartbeat.  
As pregnancy progresses, the ultrasound is used to check the baby’s anatomy, their growth, health and location of the placenta.
How is an ultrasound carried out?
The pregnant mum to be raises her top up to under the bust and opens the top of their trousers pushing them down slightly.  A clear gel is rubbed onto the belly and then a probe known as a transducer is rubbed over the tummy area. The transducer emits sound waves which bounce off the baby to create an image which you view on the ultra sound machine screen.
There are times in early pregnancy where you may require a transvaginal (or internal) ultrasound.  This is a trousers/pants off procedure and the sonographer inserts a skinnier probe, covered in a condom and lubricant into the vagina. The exact same technology of sound waves is used here but it allows the sonographer to see the fetus before it can be seen on a transabdominal ultrasound. This is frequently used in early assessment units, when miscarriage is suspected.
When is an ultrasound carried out in pregnancy?
Depending on what health care provider you opt for though, you may have your pregnancy confirmed at 12 weeks by anything from a Doppler heartbeat monitor all the way to a super doper 3D ultrasound machine.  Many private consultants now have scanning machines in their office which means mum to be can get a look at the baby during each visit.
A woman will usually have one definite ultrasound during her pregnancy around 20 weeks.  This is a detailed anatomy scan – it’s at this time that your sonographer will measure your baby and give you those little black and white grainy photos. As pregnancy progresses, there may be a requirement to have further scans such as if multiples are being carried, to check the position of the placenta and it is used in other tests such as amniocentesis.
Are there any risks?
Ultrasounds are not associated with any risks however medical guidelines caution against unnecessary exposure to ultrasounds. 
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