Patter of tiny beat

Technology that could save the lives of unborn children has been developed at

. The small device, no larger than a mobile phone is able to monitor a baby's heart for signs of any potential defects or problems.

The new system has taken 15 years to develop and resulted in the researchers behind it — from the university's school of electrical and electronic engineering department and the school of human development — setting up a spin-out called Monica Healthcare.

Dr Barrie Hayes-Gill, who is in charge of the spin-out and also helped develop the core technology, said he believes the system could one day help around 70,000 babies a year in the UK alone.

Real challenge

The device works by monitoring the tiny electrical signals which are produced by an unborn baby's heart. It operates in much the same way as a conventional adult ECG, except that the signals that must be detected are around 5,000 times smaller, said Hayes-Gill.

'The real challenge is trying to pick up on signals which are as low as 200 nanovolts or 0.2 microvolts,' he said. 'These are really tiny signals and so you need to ensure that you are able to reject other non-foetal activity.'

The palm-sized device is said to be extremely simple to use. Electrodes are placed on the expectant mother's stomach to pick up the faint signals from the baby's heart. Because the device is so light, it can be carried by the mother all day as its on-board computer filters out the relevant data which is then transmitted wirelessly to a nearby PC or hand-held computer.

The three channels in the device are able to record the real-time data over a 24-hour period — a crucial difference when compared with existing baby-monitoring technologies, according to Hayes-Gill.

Hospitals currently use ultrasound to monitor heart rates during pregnancy. While the technology is undoubtedly effective it can only monitor pregnant women when they visit the hospital — typically once a fortnight for 'at-risk' mothers who may have medical conditions such as diabetes or autoimmmune problems. This can mean that rare events in the baby's development will not be picked up as they occur.

There are a number of other disadvantages of using ultrasound. The process means directing beams of sound at the foetus with a high-frequency signal which can be potentially harmful. The technique also produces an average heart rate reading, which is not as accurate as measuring each and every one.

Monica Healthcare's system will be the first to offer routine, continuous long-term monitoring, which is entirely safe, it is said.

'There are periods of inactivity for the mother over a 24-hour period where the background noise is low and the signal can be picked up much more clearly,' said Hayes-Gill.

This data is filtered with in-built software, which has been optimised to be able to extract the baby's ECG readings from amid the much louder background noise of the mother's.

Key feature

This 'noise-management' is one of the key features of the system, said Hayes-Gill. The system is also able to determine the baby's position in the womb based on this signal.

'Ultrasound cannot be carried out continuously and it means the mother has to be hooked up to a machine, whereas with our system she can just attach a device no larger than an iPod to a belt strap,' he said. 'This gives the mother much more freedom to continue her daily routine.'

After passing EU safety standards the system is now undergoing clinical trials in Holland, which are expected to be completed by the end of July. Hayes-Gill has estimated that the device will be read to go on sale by October this year, a turnaround from research to medically approved product within only two years.

Hayes-Gill added that this rapid process of getting a product to market will be invaluable experience for any future medical devices the spin-out may hope to commercialise.