Special Delivery

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Occasionally during birth, the stresses involved dangerously deplete the amount of oxygen reaching the fetus from the mother. That's why for more than a quarter century a cardiotocography (CTG) unit, which monitors heartrate, has been standard equipment in maternity rooms. But doctors often find CTGs of limited value because their data can be difficult to analyze, says Arne Samuelsson, technology director of Neoventa Medical, a Gothenburg, Sweden, company that's developed a new fetal heart monitor system it calls STAN S21.

Twenty-five percent of the time, the CTG is clearly accurate in showing that the newborn is perfectly fine; and 25% of the time, it is also 100% accurate in showing that the child is in danger of suffering from oxygen deficiency, which can cause serious damage. But half the time, Samuelsson says, the information coming from the CTG falls into a "gray zone" and is hard to interpret. That means doctors can sometimes miss entirely the fact that a child is in danger, or — more likely — it will force them to take unnecessary intervening procedures, "just in case."

These can include Caesarean sections and forceps deliveries, which are also more risky to mother and child, and can increase costs.

What Neoventa's STAN system adds is digital signal processing technology that can accurately conduct waveform analyses of the ECG (electrocardiogram) reading. That means it focuses on the relaxation phase of the heartbeat, known as the ST interval. "This illustrates how much stress the fetal heart can withstand if there is a temporary reduction of oxygen," Samuelsson explains. "We can see when a fetus enters a more serious state of stress." The concept of monitoring and analyzing the ST interval to provide better maternity-room data has been known for around 30 years. But only because of recent breakthroughs in microchip technology have researchers been able to build a machine that could perform the task. It could have been done a decade ago, Samuelsson says, but the product would have been too slow and too expensive.

The STAN system has undergone two, independent clinical trials. Each showed it "substantially" reduces incidences of oxygen deficiency in newborns, as well as the number of acute interventions. And Samuelsson says feedback from physicians and midwives who have used the system has also been very good, and it improves the longer they use it. While learning how to read the data can be taught in a day, results improve as doctors become more confident in relying on it. "There is an educational curve," he says.

So far, Neoventa has installed 150 systems in Europe, mainly in Nordic countries. But it anticipates obtaining pre-market approval from the U.S. Food and Drug Administration shortly, a necessary regulatory step for breaking into the vast American market. Since the U.S. comprises half the global market for medical devices, Neoventa is eager to begin deliveries there as soon as possible.