Trauma claims on the rise for caesarean deliveries complicated by 'impaction of the fetal head' in second stage of labour

A research study has recently been launched to find out more about the rising numbers of second stage caesarean sections in the UK which are complicated by impaction of the fetal head and in turn lead to injury to both mother and baby.

What is the second stage of labour?

The second stage of labour starts when the mother’s cervix has opened to 10cm and is fully dilated. In a vaginal delivery, this is the stage where the mother pushes the baby out. The second stage of labour ends when the baby is born.

Why are second stage caesarean sections a problem?

Around a quarter (26%) of all deliveries in the UK are caesarean sections. Increasing numbers of these (estimated at 5% of caesareans and 2% of all deliveries) are carried out as emergency c-sections in the second stage of labour.

Emergency caesarean section in the second stage of labour has a greater risk of complications for both the baby and the mother than elective (planned) caesarean section or when the c-section takes place earlier in labour.

Delivery by caesarean section after the cervix is fully dilated is more difficult, even for experienced obstetricians, as the unborn baby’s head has descended further into the mother’s pelvis where it becomes wedged (impacted or deeply engaged). 

Complications can arise from the manipulations that are needed during caesarean section to free the baby’s head from where it is wedged within the pelvis. There is little room for the obstetric surgeon to place their hand between the pelvis and the fragile fetal head and this may be made even more difficult when there is moulding (movement of the bones of the skull) of the baby’s head which often takes place in labour. The surgeon needs to act quickly to deliver the baby to avoid risk of serious injury to the baby’s brain but must also take care to avoid injury to the mother’s uterus which will by now be stretched and thinned from labour, making it prone to tearing. The risk of injury to the mother’s uterus is even greater where second stage caesarean section follows an unsuccessful attempt at (vaginal) instrumental delivery.

The number of compensation claims for injuries suffered by mothers and babies during negligently managed second stage caesarean sections with an impacted fetal head are rising. Commonly suffered injuries to the baby include:

• skull fracture;
• intracranial haemorrhage;
• hypoxic (oxygen deprivation) brain injury;
• death.

Maternal injuries include:

• uterine tears;
• damage to the uterine artery;
• haemorrhage;
• bladder and bowel injuries;
• difficulties with future pregnancies.

There is currently no national guidance in relation to best practise or safe techniques for management of an impacted fetal head at caesarean section.

How does the fetal head become impacted in labour?

The descent of the baby’s head into the mother’s pelvis happens naturally in labour to place the baby in position for delivery via the birth canal.

The fetal head can become impacted and vaginal delivery obstructed if the baby is incorrectly positioned. Maternal obesity and the size of the baby’s head are also thought to increase the risk of fetal head impaction.

Prolonged labour (particularly in the second stage) also increases the risk but, in most cases, current guidelines for the management of labour recommend that if there is lack of progress in the first stage (before the cervix has fully opened), the uterine stimulant, Syntocinon, should be used to try to stimulate uterine contractions and speed up labour before a caesarean section is considered. In the meantime, as the labour progresses to second stage, the baby’s head can become more deeply impacted.

In the second stage, assisted vaginal delivery may then be attempted with forceps or Ventouse suction which, if unsuccessful, delays the delivery further and increases the risks of injury during second stage caesarean section to both mother and baby.

How does injury occur during delivery involving impacted fetal head?

As with any difficult procedure, the risk of failure and harm is increased where the person attempting the procedure is inexperienced. A national survey revealed that over 60% of training grade (below consultant) obstetricians have had no training, whether in live situations or by simulation, for handling the delivery of a baby where there is an impacted fetal head. Many junior obstetricians have to deal with this emergency situation for the first time without prior training, often at night when there is no immediate access to help from a senior, more experienced colleague. 

The choice of technique can also increase the risk of injury. Various procedures have been developed to achieve delivery of a baby where labour is obstructed by an impacted fetal head, including reverse breech extraction (in which the baby is delivered at caesarean section by a ‘pull’ procedure similar to a vaginal breech delivery), and more common but increasingly controversial ‘push’ techniques.

‘Push’ techniques which put pressure on the baby’s skull - such as the common practise where the operating surgeon attempts to put their hand between the baby’s head and the mother’s pelvis to disengage the head whilst an assisting doctor or midwife pushes the head upwards via the vagina – can cause skull fractures, brain injury or result in the baby’s death. Where this ‘push’ technique has been carried out in a way that has caused traumatic injury to the baby, there may be grounds for a negligence claim.

In second stage caesarean sections involving impaction of the fetal head, as with all obstetric emergencies, simulation exercises, staff training, early recognition of risk in labour (and early action), and multi-disciplinary teamwork under the leadership of a senior obstetrician are essential for the safety of mother and baby.

What is being done about fetal impacted head caesarean safety?

In March 2019, the MIDAS study of Impacted Fetal Head at Caesarean Section began a six month surveillance study during which it will use the UK Obstetric Surveillance System (UKOSS) to find out:

• how many second stage caesarean sections with impacted fetal head are being carried out in the UK;
• the circumstances in which these complications arise;
• if there are identifiable risk factors for impacted fetal head;
• the techniques used to disengage the fetal head;
• the extent and type of birth trauma (injury) which occur in these deliveries;
• maternal outcomes in these cases.

Boyes Turner’s birth injury specialists await the outcome of this study with interest, in the hope that the information it provides will raise awareness and inform current practise, encourage mandatory maternity staff training and result in safety guidelines, reducing the avoidable harm caused to mothers and babies.

If your family has been affected by serious injury to mother or baby during childbirth and you would like to find out more about bringing a claim, contact us by email at cerebralpalsy@boyesturner.com.