Ultrasound scan is a useful diagnostic tool, which can provide pregnant women detailed examination of fetal structures. A special gel will be rubbed onto your abdomen to reduce signal loss, and then a probe/transducer will be placed onto your abdomen, which can emit and receive ultrasound waves. Those waves are assembled into a picture on a screen, and you can see the moving structures such as fetal heart. To improve image quality, you need to have a full bladder before an ultrasound scan in the first 3 months of pregnancy. So drink plenty water or fresh juice.


Ultrasound is safe for you and your baby, and is an important part of antenatal care. Ultrasound scan can monitor fetal growth and wellbeing, locate the placenta, and guide invasive procedures. An ultrasound scan in early pregnancy can confirm the viability of your pregnancy by detecting a fetal heart beat at 5-6 weeks. By measuring the thickness of the fat pad at the back of the neck at 11- 14 weeks, ultrasound scan can also screen the fetus for chromosomal abnormalities, e.g. Down's syndrome. At 18-20 weeks, you will get detailed scan, which aims to examine each part of your baby carefully.


The use of ultrasound in pregnant women was pioneered by Scottish Professor Ian Donald in the late 1950s. And now as technology improves, 3D ultrasound is also available, which provides clear pictures of the baby, and you can even see the face clearly.