Your Gynaecologist will direct soundwaves towards the area of your body to be viewed with a wand-like instrument called a transducer. The transducer emits very high-frequency soundwaves which can travel easily through your pelvis. The soundwaves bounce off the fluids, tissues, and bones, which allows the transducer to detect their size, shape and location. This is not unlike dolphins’ ability to sense their surroundings using echolocation. During your screen, you’ll be able to view the images on a screen, aggregated to show motion. You can also take home still-frame “photos” of your growing baby if you wish.

An ultrasound can tell your doctor a lot about the foetus and your pregnancy, including:

• Its size and approximate age
• Its position and orientation in your uterus
• Its heart rate and respiration
• The volume of amniotic fluid
• The location and size of the placenta

An ultrasound can also tell whether you are carrying a multiple pregnancy (twins, triplets, or more). It can also screen for certain birth defects or ectopic pregnancy.Other non-obstetrical uses for an ultrasound screen include diagnosing tumours, cysts, and polyps, and rooting out causes of pain and menstrual problems.

Yes. Each type of ultrasound was developed to better provide your doctor with the type of image needed to evaluate your condition.

TRANSABDOMINAL

For this type of ultrasound, your London Obs & Gynae Consultant will squirt an amount of clear jelly on your belly and glide the transducer across the abdomen. The jelly acts as a soundwave conduit between the transducer wand and your tissue. You should wear a loose-fitting shirt and drink plenty of water a few hours before your transabdominal ultrasound. Drinking fluids will fill your bladder, pushing the uterus up past the bowels and towards the abdominal wall, making the foetus easier to see.

TRANSVAGINAL

In this procedure, the transducer wand is inserted into your vagina. This type of ultrasound can generally see more of your pelvic organs than a transabdominal ultrasound, and may be more useful in the first trimester when the foetus is still very small.You will be asked to undress from the waist-down, and to lie on your back and place your feet in the stirrups, much like during a normal pelvic screen. The transducer will be covered in a lubricated latex sleeve to make it easier to slide into your vagina.

3-D AND 4-D ULTRASOUND

These are transabdominal ultrasounds that take hundreds of images simultaneously, and aggregate them into a three-dimensional model, with or without showing movement.

DOPPLER

A Doppler ultrasound can detect the circulation of blood in the placenta and umbilical cord. This is the type of ultrasound that can allow you to hear your baby’s heartbeat.