Latest HSIB report: severe brain injury, neonatal death and stillbirth from maternity care of big babies and shoulder dystocia

The Healthcare Safety Investigation Branch (HSIB) has published its latest national learning report into maternity safety: Severe brain injury, early neonatal death and intrapartum stillbirth associated with larger babies and shoulder dystocia. The report sets out the lessons to be learned from 31 HSIB investigations arising from births complicated by shoulder dystocia which led to the death of the babies or brain injury from HIE.

The increased risk of shoulder dystocia to big babies was one of the emerging maternity safety themes that HSIB identified as needing further investigation in their March 2020 report, Summary of Themes arising from the Healthcare Safety Investigation Branch Maternity Programme. The latest report looks at the factors in pregnancy, labour and birth that increase the risk of shoulder dystocia for larger babies. It calls for RCOG guidance to address inconsistencies in the way that maternity services identify big babies and manage their mother’s maternity care.

What is shoulder dystocia?

Shoulder dystocia is an obstetric (childbirth) emergency. It occurs when the baby’s head has been delivered but their shoulder becomes wedged behind the mother’s pubic bone preventing delivery of the baby’s body. According to HSIB, shoulder dystocia affects 3,770 to 4,550 births in England each year but, if properly handled, usually does not lead to long term injury.

When delivery is obstructed by shoulder dystocia, the maternity team must act quickly to perform specific manoeuvres to release the baby from its stuck position and deliver the baby. Poor management of shoulder dystocia can cause bleeding and perineal injury to the mother. Excessive force or traction (pulling) on the baby can cause fractures to the baby’s arm or collar bone, or brachial plexus nerve injury (Erb’s palsy). Delays can cause hypoxic (lack of oxygen) brain injury or death to the baby from compression of the umbilical cord between baby’s body and the mother’s pelvis, or of the blood vessels in the baby’s neck, or premature separation of the placenta.

Shoulder dystocia can happen during any birth, but bigger babies have a higher risk of traumatic injury, brain damage or death from their shoulders getting stuck during birth. The risk of shoulder dystocia is also higher where the mother has had previous shoulder dystocia, gestational diabetes or a high BMI, where labour is induced, prolonged or augmented with oxytocin (syntocinon), or assisted with forceps or Ventouse delivery.

HSIB’s report – 31 babies suffered brain injury or death after shoulder dystocia at birth

31 (9.5%) of HSIB’s 326 completed maternity investigation reports involved babies who were injured after shoulder dystocia at birth. These represented 11% of all babies with HIE who were reported to HSIB. Two of the 31 babies were stillborn as a result of the shoulder dystocia. One newborn baby died from health conditions unrelated to the shoulder dystocia. The other 28 babies were diagnosed with HIE and were treated in neonatal intensive care with cooling. Shoulder dystocia was the main cause of most of these babies’ hypoxic brain injury.

HSIB’s maternity investigation reports into these 31 babies’ maternity care were reviewed by a panel including obstetricians, midwives and neonatologists. The report sets out their findings and recommendations to improve the maternity care of women at risk of shoulder dystocia in pregnancy.

Theme: inconsistent identification and management of large babies during pregnancy

The risk of shoulder dystocia and the identification of a ‘large’ baby should take into account the mother’s height, weight and maternity history. HSIB found a lack of consistency across maternity services in how they identified and then managed the antenatal care of mothers suspected to be carrying larger babies. Guidance varies about the weight at which a baby is classified as large for gestational age (pregnancy dates). Some guidance says 4,000g whereas others say 4,500g.

The birthweights of the 31 babies ranged from 3,565g to 5,177g. NHS maternity statistics for England say that 10% of babies had a birthweight of more than 4,000g in 2019 to 2020, but HSIB found that 22 (71%) of the 31 babies who were injured after shoulder dystocia weighed more than 4,000g at birth. Eight out of the 22 mothers were not identified as having a large baby by ultrasound before birth and missed out on having a growth scan even after having unexpectedly high ‘symphysis fundal height’ (SFH) measurements of the uterus size in some cases.

Guidance about growth charts, which are used to measure and track the baby’s size, leave it up to trusts as to how to manage the care of suspected big babies. When an unborn baby is suspected to be large from SFH measurements, HSIB found a wide variation in the follow up actions taken by each trust. Some trusts do not refer the mother for a growth scan. Others do, but not all then investigate further and discuss with the mother her options for birth.

The guidance on induction of labour (IOL) for shoulder dystocia is contradicted by a Cochrane review which found that IOL, rather than waiting for spontaneous labour to begin, reduced the number of births affected by shoulder dystocia and recommended further research to help reduce avoidable harm.

NICE guidelines recommend that mothers who are suspected to have a large baby should be under obstetric-led (doctor-led) care and give birth in an obstetric-led unit. The latest NICE guidelines on labour and birth care for women with existing medical conditions or obstetric complications advises that these mothers are at increased risk of complications in labour such as shoulder dystocia, brachial plexus injury, assisted birth or caesarean section. Women in labour with suspected large babies should be offered the option to continue, to augment (boost) the labour, or to have a caesarean section.

Theme: screening for gestational diabetes

Babies of mothers with diabetes are often bigger and have two to four times the risk of shoulder dystocia compared with babies of the same birthweight born to mothers without diabetes.

HSIB found that some women who are at risk miss out on screening for gestational diabetes, which is carried out only on mothers with specified risks. These include high BMI, gestational diabetes in a previous pregnancy, a previous large baby, very close relatives with diabetes or BAME family origins with a high prevalence of diabetes. There is no national guidance on how to screen mothers for gestational diabetes late in pregnancy (third trimester) when it usually occurs. Mothers with babies over 4,000g miss out on screening and also the individualised discussion about risks, benefits, and birth choices, including IOL or caesarean section, that should follow a diagnosis of gestational diabetes and the identification of a large baby.

Theme: sharing information with mothers

Mothers with large babies are more likely to have an assisted (forceps or vacuum) birth or caesarean section. The baby also has an increased risk of shoulder dystocia and birth injury. However, HSIB found that even though 14 of the 31 babies were suspected to have a predicted birthweight of over 4,000g after a growth scan, 10 of those 14 mothers had no discussion about the increased risk of shoulder dystocia and its implications for labour and birth. Some women with high SFH measurements had neither a growth scan nor an estimate of the baby’s weight before birth and no discussion about how their raised SFH might affect labour and birth.

HSIB reiterated that the law, set out in the case of Montgomery v NHS Lanarkshire (a shoulder dystocia birth injury claim where information was withheld from a mother about her risks, which would have resulted in her choosing a caesarean section) requires healthcare professionals to inform the mother of the risks and benefits of different birth options in pregnancy so she can make an informed choice about her care. The General Medical Council’s 2020 guidance on decision making and consent also reiterates that shared decision-making and informed consent are fundamental to good practice.

Theme: place and mode of birth

Shoulder dystocia is associated with prolonged labour and assisted vaginal birth. Guidelines state that labour and birth should be transferred to obstetric-led care if a big baby is suspected during pregnancy or in labour.

HSIB found that 6 of the 31 mothers gave birth in a midwife-led unit. Two had pregnancies with suspected big babies but both remained in a midwife-led setting without counselling or discussion about complications. They should have been transferred to obstetric-led care in line with NICE guidance.

Theme: Recognition of shoulder dystocia

HSIB found evidence of delayed recognition of potential shoulder dystocia. When signs of potential shoulder dystocia were missed, such as slow or difficult delivery of the baby’s head, this led to a delay or failure to summon additional obstetric or neonatal help. In 4 of the 31 cases the neonatal team was not present for the birth of the baby. Where shoulder dystocia was recognised, maternity staff failed to respond appropriately by using the national emergency 2222 call system.

HSIB reiterated that delay in calling the neonatal team is a common feature of maternity safety reports and recommended that neonatal involvement and anticipation of shoulder dystocia should be a focus of multi-disciplinary team training.

Theme: injuries to babies following shoulder dystocia

Hypoxia can be caused by compression of the umbilical cord or the baby’s neck and by separation of the placenta during a prolonged shoulder dystocia. In the 31 cases reviewed, it took between 2 to 25 minutes to deliver the body after delivery of the baby’s head. Whilst most of the babies’ umbilical cord blood gas results (often used to detect oxygen deprivation in a newborn baby) were normal, these babies were born in poor condition and needed resuscitation, which suggests that compression of the umbilical cord vessels had completely blocked the transfer of oxygen to the baby during the shoulder dystocia. Some babies’ umbilical cord blood gases showed a profound and prolonged hypoxia after only a short delay in delivery, suggesting that their oxygen deprivation began before shoulder dystocia occurred. Shoulder dystocia was a contributory factor to the baby’s condition.

Six of the 31 babies sustained additional birth injuries. Three babies had brachial plexus (Erb’s palsy) injuries and three had a fractured humerus (upper arm bone).

Boyes Turner are committed to helping families obtain compensation after birth injury

Boyes Turner’s birth injury and cerebral palsy team welcome HSIB’s efforts to raise awareness of the importance of identification and management of pregnancies at risk of shoulder dystocia, in the hope that fewer babies and mothers will suffer avoidable harm. Once potential risks are identified, parents have the right to be informed of the risks and have a say in their care options. When mistakes lead to injury, the impact on the child and their family is lifelong and devastating, and they must be fully compensated for their avoidable harm.

If you or your child have suffered a birth injury and would like to find out more about making a claim for compensation, contact us by email at cerebralpalsy@boyesturner.com.