Heart rate monitors 'can put unborn babies at risk'

Published on 18/08/2009 22:03

PREGNANT women were yesterday warned against using foetal heart rate monitors at home.

Experts said that the devices may cause delays in women seeking help if their baby stops moving.

Writing in the British Medical Journal (BMJ), they told how one woman used a foetal Doppler machine after her baby's movements slowed but felt reassured all was well after hearing the heartbeat.

However, the baby girl went on to be delivered by emergency caesarean and stayed in a special care unit for eight weeks.

She is now making steady progress.

Foetal Doppler machines enable expectant parents to hear the movements of their unborn child from around the 12th week of pregnancy.

As well as the heartbeat, the machines are advertised as making it possible to hear hiccups and the baby kicking.

Some machines have a recording cable so people can save the sounds on to a computer or CD.

Today, Dr Thomas Aust, a specialist registrar, David Ankers, a trainee specialist and Akin Famoriyo, a consultant, all from the department of obstetrics and gynaecology at the Wirral University Teaching Hospital NHS Foundation Trust, issued a warning to pregnant women about the machines.

"A 27-year-old presented to our labour ward at 8pm, 32 weeks into her first pregnancy with reduced foetal movements," they said.

"She had first noted a reduction in foetal activity two days earlier but had used her own Doppler device to listen to the foetal heartbeat and reassured herself that everything was normal.

"A foetal cardiotocograph was not reassuring and showed reduced variability for over an hour. Steroids were given to enhance foetal lung maturity, and the baby was delivered by caesarean section later that evening."

The baby was born floppy and small for gestational age, while the placenta "looked calcified and pale".

The baby remained in the special care unit with hypoxic ischaemic encephalopathy, which is damage to the cells of the nervous system, and intraventricular haemorrhage, which is characterised by poor reflexes and lethargy.

The experts went on: "The current guidelines from the National Institute for Health and Clinical Excellence (Nice) on detection of foetal wellbeing do not support the routine counting of foetal movements.

"But most obstetric units would encourage patients to attend for a cardiotocograph and possibly further ultrasound assessment of growth and foetal activity if episodes of reduced movements recur.

"A hand-held Doppler device assesses the presence of foetal heart pulsations only at that moment, and it is used by midwives and obstetricians to check for viability or for intermittent monitoring during labour.

"In untrained hands, it is more likely that blood flow through the placenta or the maternal aorta or iliac vessels will be heard."

An internet search revealed that a foetal Doppler machine could be hired for 10 a month or bought for 25 to 50 on eBay.

The experts said: "Although the companies offering sales state that the device is not intended to replace recommended antenatal care, they also make claims such as, 'You will be able to locate and hear the heartbeat with excellent clarity'.

"Although self-monitoring provided false reassurance and a delay in seeking help in this case, it is difficult to say if this altered the outcome.

"We now have posters in our antenatal areas to recommend that patients do not use these devices."