First it's important to explain what ultrasound is. Any signal from a frequency of 1MHz is classified as ultrasound. However, the tabloid press classify all units as ultrasound from the very high power therapy machines, through ultrasound imaging systems for looking at your unborn baby, to fetal monitoring machines and small pocket dopplers for listening to your baby's heart beat.

There are very big differences between all these machines.

So is it safe ?

There have been no studies that have shown that fetal monitors or fetal heart detectors have produced any cell damage or any effect that could show harm to the unborn baby.

Tests and studies are not of course all the evidence, fetal heart detectors have been used daily for the last 30 years and we estimate that there are around 5 million in use each and every day with no adverse reports.

So why do the press say ultrasound causes damage ?

The analogy we use is that it is quite safe to place your fingers on a 9V battery but if you hold the bare ends of a mains cable it WILL hurt !

The same is true for ultrasound, the output levels from pocket fetal dopplers are around 0.01 watts of power where as ultrasound imaging is around 0.5 watts with pulse powers which could be even higher.

It is certainly unwise to expose your baby to unnecessary risks but to listen to your baby with an ultrasound doppler can reduce maternal stress, increase bonding with your partner and unborn baby's siblings.

Maternal stress has been linked to a significant risk to the health of the unborn baby.