Baby Heartbeats

(SFX: Heart beats)

     DURING PREGNANCY DOCTORS REGULARLY USE ULTRASOUND TO MONITOR THE
HEALTH OF A GROWING FOETUS.  BUT IF THERE ARE ANY COMPLICATIONS AND THE
MOTHER NEEDS REPEATED TESTS, ULTRASOUND CAN GET EXPENSIVE AND TIME
CONSUMING. 

     Zahorian: "Typically, the high risk mothers are coming in 2-3 times a week to a
clinic, which is a nuisance."
     
     ELECTRICAL ENGINEER STEPHEN ZAHORIAN AT OLD DOMINION UNIVERSITY IS
WORKING ON A PORTABLE SYSTEM TO MONITOR FETAL HEART BEATS.  THE SYSTEM LOOKS
LIKE A WIDE BELT TO WRAP AROUND YOUR WAIST AND IT SENSES THE MINUTE SOUND
WAVES OF THE UNBORN BABY'S HEART.  THE SOUNDS ARE SO SOFT--ESPECIALLY
COMPARED TO THE OTHER NOISES PRODUCED IN THE MOTHER'S BODY-- THAT IT'S HARD TO
LISTEN FOR THEM, BUT THEY NEVERTHELESS PRODUCE MINI-WAVES THAT ROLL THROUGH
THE MOTHER'S BODY.  ZAHORIAN'S BELT SENSES THESE ALMOST IMPERCEPTIBLE MINI-EARTHQUAKES ACROSS THE MOTHER'S SKIN. 

     Zahorian: "The front end is a bit like a stethoscope in the sense that we're really
listening to the heart beat.  but unlike a stethoscope we have several different sensors. . .
.  These sensors. . . convert the acoustic pressure to a little minute electrical signal." 

     THE SENSOR IS BASED ON SOMETHING CALLED A PIEZO-ELECTRODE WHICH WHEN
IT'S COMPRESSED--SAY BY THE SLIGHT MOVEMENT OF THE MOTHER'S SKIN--SENDS OUT A
FLASH OF ELECTRICITY. THE ELECTRICAL PULSE TRAVELS TO A COMPUTER WHICH CAN
DISPLAY THE HEARTBEAT ON SCREEN.  
     THE SIMPLE BELT HOOKED UPTO A COMPUTER MEANS THAT HIGH RISK MOMS
COULD ONE DAY CHECK THEIR FOETUS'S HEARTRATE  WITHOUT HAVING TO TREK TO THE
HOSPITAL TWICE A WEEK.  TRIAL TESTING OF THE NEW TECHNIQUE IS GOING ON NOW IN
LOS ANGELES.