More than 100 women suffered from potentially fatal blood loss when giving birth at the Bradford Teaching Hospitals NHS Foundation Trust in just one year.

A landmark audit of maternity services across Great Britain has uncovered "unexplained variation" in the number of women sustaining severe birth complications, including major postpartum haemorrhages, one of the most common causes of maternal deaths.

Campaigners say the experiences can have a severe impact on women's mental health, and may even lead to post-traumatic stress disorder.

According to the National Maternity and Perinatal Audit, 105 out of 4,868 women (2.4%) suffered a haemorrhage in which they lost at least 1,500ml of blood when giving birth at the Bradford Teaching Hospitals NHS Foundation Trust, which runs BRI, in 2016-17.

A further 1,477 women (31.2%) suffered haemorrhages in which they lost at least 500ml of blood.

This was below the national average, however, where the rate rose as high as 5.4% in North Bristol, the worst performing trust.

Kim Thomas, chief executive of charity the Birth Trauma Association, said losing a lot of blood could leave women feeling very weak and struggling with milk production, and could be the cause of post-traumatic stress.

"A lot of women feel unprepared for the things that can go wrong in childbirth and sometimes blame themselves for events that were out of their control," she said.

"A postpartum haemorrhage is a medical emergency. Typically, the midwife will ring a bell and other staff members will come rushing into the room.

"Because women don’t always know what’s happening, other than that something has gone wrong, it can be an incredibly frightening experience, and is often the focus of women’s PTSD flashbacks.

"It’s really important that women go into childbirth fully informed."

Across Great Britain, 2.9% of all women who gave birth suffered at least 1,500ml of blood loss, but for those who had a caesarean section the rate increased to 4.3%.

Women who are obese, have a long labour, or who have their first baby after they turn 40 are more likely to suffer a postpartum haemorrhage.

However, the audit found the geograophical variation was beyond what would be expected based on demographic factors alone.

The Royal College of Obstetricians and Gynaecologists, which led the national audit, called on healthcare workers to use the figures to drive improvements to service quality.

Professor Lesley Regan, RCOG president, said: "All women should expect to receive the best possible care during pregnancy and childbirth.

"National initiatives to improve maternal and neonatal care are making impressive headway to ensure services are as safe and personalised as possible for women, the vast majority of whom have a safe birth.

"But we must not be complacent since this report highlights marked variation in standards of care persist, particularly around birth complications."