Women who experience a sudden and unusual episode of foetal activity before giving birth are at an increased risk of stillbirth, an international study has found.
Pregnant women are often told to seek medical care if they have concerns about changes in the movements of their unborn babies to help prevent perinatal deaths.
But new research has found it is not only a decrease in movements that mothers need to be aware of.
Researchers behind the study, including Associate Professor Jane Warland from the University of South Australia, hope the findings will help reduce the rate of stillbirths in Australia.
"The main difference was the people who had told us they'd had a stillbirth, about a quarter of them actually said that their baby had a period of activity just once," Dr Warland said.
"The baby went 'crazy', 'wild', 'ballistic', 'nuts'. Those sorts of words were the words that the [study's] participants used.
Dr Warland hopes the research, published in BMC Pregnancy and Childbirth, will raise awareness and encourage women to seek help if they have any concerns during pregnancy.
"Our advice is don't be afraid. The hospital is open 24/7. Ring them, go and be checked out," she said.
"As a midwife myself, I would much rather reassure you 1,000 times than have to say those horrible words, 'I'm sorry, there's no heartbeat'."
Pregnant women urged to seek help
The research confirms what many mothers have told Claire Ford, chief executive of Still Aware, a not-for-profit organisation that raises awareness of stillbirths.
"We've been listening to women tell us that their baby's movements changed, that it wasn't just about my baby decreasing in movement before the baby was stillborn," Ms Ford said.
"It's about saying my baby's movements are different from what's normal for my baby.
"So we have been really talking to expectant mums and clinicians about really listening to women and encouraging clinicians to empower families to feel like they can come in at any time."
Ms Ford said she hoped the research's findings would help prevent stillbirths in the future.
"Stillbirth is an utter tragedy because it's happening at once. You're saying hello and goodbye to a baby that you we're expecting to take home and to fill your home with love," she said.
"Every day in Australia six babies are stillborn, so that is six families that have to go through that tragedy."