More than 20 NHS trusts and health boards in the UK should investigate why they have a higher stillbirth and newborn baby death rate than their peers, an inquiry has recommended.

The trusts and boards should review their maternity care to find out whether mistakes were made or if there were other reasons for a death rate that was more than 10% higher than average, said a national team of experts from MBRRACE-UK (Mothers and Babies: Reducing Risk Through Audits and Confidential Enquiries Across the UK), led by the University of Leicester.

It is the first time potential issues in childbirth have been highlighted at individual trust level. Out of 162 trusts and boards, 21 have been red flagged by the investigators and told they should hold a review. A further 52 have an orange flag, which means they are advised to consider a review.

“These data provide NHS trusts and health boards from around the UK with the clearest insight yet in helping them understand their performance against their peers. Whilst there is always room for improvement, the data flags those trusts and health boards which need to review their performance as a priority,” said Prof David Field, from MBRRACE-UK.

The data is from a further analysis of information that was collected by MBRRACE-UK for its report published in June, which showed the UK lagged behind comparable countries for stillbirths and neonatal deaths – defined as within 28 days of birth. It also showed that pregnancies in women living in the UK’s poorest areas were over 50% more likely to end in stillbirth or neonatal death.

Identifying the trusts and boards with higher than average deaths and stillbirths risks causing anxiety both among maternity staff and women planning to give birth there, acknowledged Field, but a red flag does not necessarily mean a problem.

“One big confounding factor is congenital abnormalities,” he said. “We have clusters where mums won’t consider a termination so the baby dies in hospital.” The team has taken into account the poverty of the area, so deprivation in itself is not a reason why a trust might be red flagged.

“This report gives us a snapshot of baby deaths across the country and what it tells us is that there is huge variation, even when you compare like-for-like units,” said Charlotte Bevan, the senior research and prevention adviser at Sands, the stillbirth and neonatal death charity. “The question we need to answer is why. We know from the recent national confidential inquiry that 60% of babies who die before they are born and close to their due dates might have been saved if basic guidelines in antenatal care were followed.”

The publication of the data came as an NHS survey showed that one in seven women is left alone and worried during early labour, while only half get the support they need immediately after birth.

The poll of 20,000 women who gave birth in February was carried out by the Care Quality Commission (CQC) across133 NHS trusts in England. It found a six percentage point rise – from 35% to 41% – in the proportion of woman who were offered the choice to give birth in a midwife-led unit or birth centre than in 2013, when a similar survey was carried out. Confidence and trust in midwives during labour has risen from 78% to 80%.

But only two-thirds of women (64%) said they were able to get attention from a member of staff within a reasonable time when they felt they needed it and barely more than half (54%) after the birth, while 14% said they were left alone in the early stages of labour.

Some 9% were left alone and worried during the later stages of labour, and 2% were left alone and worried during the birth itself. After the birth, 8% said they were left alone and worried.

Of those who raised concerns during labour and birth, not all women (18%) felt their concerns were taken seriously.

Of those who had a normal delivery and did not require forceps or ventouse, there was a rise in the number giving birth with their legs in stirrups, from 17% in 2010 to 22% in 2015, which is contrary to best practice guidelines recommending women should be free to move about in labour.

A little more than half (54%) were always given support and advice about feeding their baby if they needed it during evenings and weekends, but 24% were not given advice “at all” – and 22% only received support sometimes.

Prof Sir Mike Richards, the CQC’s chief inspector of hospitals, said: “Every single woman deserves to be treated with dignity and personalised care when having a baby, and so I am glad that the findings suggest women are experiencing better care and treatment during pregnancy and birth.

“From our own inspection work of maternity services so far – rating just over 60% of trusts as either good or outstanding – there is no doubt of the improvement work that is still needed in order to narrow the wide gap of variation that we know exists.”

Data analysis excludes terminations of pregnancy and births before 24 weeks gestational age. Data for England, Wales and Isle of Man excludes January 2013 due to unavailability of data for that month. All rates given in tables are stabilised and adjusted rather than the crude original rates.