Fetal monitoring in labour - what monitoring is available and why is it so important?

Measuring an unborn baby’s heart rate is a very good way of checking their health during labour and birth. A normal heart rate can reassure healthcare professionals that it is safe to continue labour if no other problems are present. On the other hand, an abnormal heart rate may be a sign that a baby is in difficulty and needs help to be delivered safely.

Fetal heart monitoring errors contributed to 70% of adverse outcomes

The importance of accurate fetal monitoring during labour was recently highlighted in a report published by the NHS’s own defence organisation, NHS Resolution. The Early Notification Scheme progress report found poor fetal monitoring to be a leading contributory factor in 70% (i.e. more than two thirds) of cases where there was an adverse outcome for baby or mum. In 63% of cases there were two or more fetal heart monitoring errors, including a delay in acting on an abnormal fetal heart and/or a delay in escalation and/or an incorrect classification.

The report concludes that problems with fetal monitoring are still the major contributing factor in poor outcomes at birth, despite widespread initiatives aimed at improving the situation.

How is an unborn baby’s heart-rate monitored during labour?

There are various different methods, including:

1. Pinard stethoscope - a type of ear trumpet which the midwife places on the mother’s tummy through which she can hear and count the baby’s heartbeat (also known as intermittent auscultation);

2. Doppler (or Sonicaid) - a small, portable machine which uses ultrasound through a transmitter on the mother’s tummy to pick up the baby’s heartbeat;

3. Electronic fetal monitoring (EFM) or cardiotocography (CTG) - two belts are strapped to the mother’s abdomen and link in to a monitor that shows the baby’s heart beat and maternal contractions. This produces a continuous graph (often called a ‘trace’) of the baby’s heart rate in response to contractions.  

Fetal blood sampling (FBS)

If electronic fetal monitoring indicates there may be a problem with the baby’s heart rate then a fetal blood sample may be taken. During a vaginal examination, a scratch is made on baby’s scalp and a small amount of blood is taken for testing. There is a small risk of infection from the scratch which usually heals quickly after birth, but if fetal heart-rate abnormalities are suspected, a prompt FBS test may be vitally important. The blood results measure the level of oxygen in the baby’s blood and will show how the baby is coping with labour. The results will determine if labour can safely carry on or if an assisted birth or a caesarean section are required urgently.

Which method of monitoring will be used?

In uncomplicated pregnancies, where labour is progressing well and no problems are identified, often the only monitoring that will be done will be intermittent monitoring with a Pinard or a Doppler. Typically a midwife will listen to the baby’s heart during and after some contractions to see how well the baby is coping.

Continuous electronic fetal monitoring (EFM) is usually only recommended if:

• the mother has an epidural;
• the mother has an oxytocin (Syntocinon) drip to help speed up labour;
• there is a lack of progress in labour;
• there is a significant amount of meconium (baby poo) when the waters break;
• there are concerns about baby’s heartbeat;
• maternal high blood pressure, a temperature or a high pulse rate;
• maternal fresh vaginal bleeding that develops in labour;
• maternal pain differs from the pain normally associated with contractions;
• maternal contractions last longer than 60 seconds or more than 5 contractions occur in 10 minutes.

Reviewing and interpreting the EFM

Healthcare professionals are trained to look at the following four particular features on a fetal heart trace to work out whether or not it shows the baby is doing well:

1. Baseline rate;
2. Baseline variability;
3. Presence or absence of decelerations;
4. Presence of accelerations.

Depending on what these features show, a trace will be categorised as ‘normal’, ‘suspicious’ or ‘pathological’, and action will be taken to speed up labour/delivery depending on the category.

EFM alone is not a 100% reliable method of checking how a baby is coping with labour. Errors in its use and interpretation are all too common and traces can sometimes be classified as ‘normal’ or ‘suspicious’ when, in fact, the baby is in distress and needs urgent delivery. Even in skilled hands, not all patterns associated with distress of an unborn baby are currently known. Therefore, whilst EFM is a very useful indication of how the baby is coping, it must be considered together with other factors, such as known and anticipated risks, the history of the pregnancy, maternal health and concerns, to ensure a safe delivery for mother and baby.

As the recent NHS Resolution report highlights, despite widespread initiatives aimed at improving maternity safety and EFM interpretation skills, a significant number of babies continue to be injured at birth, many going on to develop cerebral palsy and lifelong disability.  

Boyes Turner’s nationally acclaimed birth injury solicitors have been helping families of brain damaged babies recover top level compensation awards for over 30 years. We are known for our outstanding expertise and success in complex cerebral palsy and birth-related injury claims including those involving errors in the use of fetal monitoring, its interpretation and delayed response to signs of fetal distress.

If you or someone you care for have cerebral palsy or serious neurological disability caused by medical negligence and you would like to find out more about making a claim, contact the team by email at mednegclaims@boyesturner.com