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fetal doppler

fetal doppler

The History of Fetal Dopplers

The first fetal doppler (a.k.a. fetal monitor ) was invented by noted physician Dr. Edward H. Hon in 1958 as a non-intrusive listening device using the echo of ultrasound waves to pick-up baby`s heartbeat.

The eponymous ` dopplers ` derives from the Austrian physicist, Christian Doppler (Hence the name dopplers) , whose 1845 discovery of the peculiarities of moving sound is now called the `Doppler effect`.

He explained that the perceived change of frequency in light and sound waves was due to the relative motion of the source and the observer. His ideas helped pave the way for theories including the idea that the universe is expanding, and made it possible to follow weather patterns by tracking electromagnetic radio waves.

Fetal dopplers utlilise this ` doppler effect ` to detect the baby`s heartbeat to allow expectant mothers to listen to and share the wonder of pregnancy with their family and friends.

fetal monitor

fetal monitor

How do Fetal Dopplers work?

Fetal dopplers use sound waves to pick up a baby’s heart beat in the womb. The probe transmits low ultrasonic waves which hit moving tissue, in this case the baby’s heartbeat. They bounce back and there is a slight change in pitch which is known as the Doppler shift and is the basis upon which most ultrasound procedures are based.



Is it safe to use a Fetal Doppler?

Any fetal monitor that we supply uses the same ultrasound technology that the medical profession has been using for more than 25 years. You may even have seen one already used by your midwife. There has never been any adverse affects reported, either for mother or child. Fetal Doppler 's are not the same as the ultrasound scanners used in hospital which show you images of the foetus. A fetal monitor operates using an extremely low power output. All our Dopplers are CE certified and meet all EU medical requirements.

There a many Fetal Dopplers on the market. What are the differences between them?

There are many different types of fetal dopplers on the market, but in essence, there are two main types. These are ‘Sound’ and ’LCD’ Dopplers. Both use the same technology but the Sound fetal doppler will enable you to hear the baby’s heart beat only, the LCD Fetal Doppler with give you a reading of the heart rate on an LCD screen as well as enable you to hear the heartbeat.

Should I hire or buy a Fetal Doppler?

Some women will rent a fetal doppler in the early stages of pregnancy as reassurance, before the foetus is developed enough to give more obvious signs of movement. However, we commonly find that they have enjoyed using a Doppler so much that they continue the rental right through until full term!

Other women are very keen on owning their own and will buy a Fetal Doppler outright.

The choice is entirely yours but if you are unsure about purchasing a Fetal Doppler outright, rental might be for you as it offers a more economical solution in the short term and allows you the flexibility to decide further down the line.

How early can I hear my baby?

This depends on a variety of factors but essentially comes down to technique. With correct use, a baby can be heard from as early as 10 weeks of pregnancy but you can usually hear the heartbeat from about week 12.

Do I need to use ultrasound gel?

It is far easier to pick up a baby’s heartbeat when using the ultrasound gel. It acts as a barrier between the probe and your tummy and conducts the sound more effectively so that you will hear a clearer and more audible heart rate. We recommend that you apply gel liberally when using a fetal Doppler

How do I care for my Fetal Doppler?

All our Fetal Dopplers come with a minimum of one year manufacturers warranty. A Fetal Doppler is a sensitive piece of equipment and every care should be taken to preserve the lifespan of a Doppler. After use, clean the probe using a soft cloth and replace the Fetal Doppler in it’s packaging to protect it from dust and moisture. Do not immerse the unit in liquid at any time.

What does my baby’s heartbeat sound like?

The fetal heart rate sounds like the hoof beats of a galloping horse. The fetal heart rate usually ranges from 140 to 160 beats per minute, approximately twice the maternal rate (The mother’s heart rate can be checked by taking the pulse). You will also hear a rushing wind like sound which is the placenta. In the latter stages of pregnancy you may even hear hiccups and kicks!

Delivery InformationNHS Purchase Orders Welcome

Fetal Doppler Rental from £9.95

BabyPlus Prenatal Education System


“I just wanted to say thank you as the service has been faultless and I will definitely use hi-baby again in the future and recommend you to my friends and family.”

R Needham, Leicester

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