First time mums are more conscious of what they eat while pregnant than those who have already had two or more children, a new survey has found.
The research, published in today's New Zealand Medical Journal, also revealed most mums didn't know all the foods that could potentially put their baby's life in danger.
Researchers stressed that while baby deaths from food infections were rare, they were also preventable.
The research surveyed 205 pregnant women in hospital and online during December 2017 and January 2018.
Findings showed that while the average knowledge score for food safety was 95 per cent, only 25 per cent of participants answered all questions correctly.
Most unknown unsafe foods were:
• Cakes, slices and muffins that have added cream or custard
• Salads, including fruit salads that have been made at a shop or cafe
• Cheese that is soft or semi-soft
The most worrying discovery was the high number of women who were aware of the danger foods but chose to ignore them, one of the researchers of the study, University of Otago associate professor Tony Walls said.
One in four pregnant women said they were "not concerned" by food safety in pregnancy.
While more than half of the women surveyed, reported being "very concerned", a majority of those were having their first or second baby, suggesting mums became more relaxed about food safety the more kids they had.
Walls - who is also a practising paediatric infectious disease specialist at Christchurch Hospital - said that while foodborne illnesses aren't common, they can be deadly for babies by miscarriage, pre-term delivery or stillbirth.
Listeriosis is the most common foodborne infection leading to baby deaths.
A previous study conducted by Walls and research, led Emma Jeffs - who is a junior doctor at Christchurch Hospital specialising in pregnancy - found that between 1997 and 2016, there were 147 pregnancy-associated cases of listeriosis in New Zealand.
There were also 22 deaths in children aged 28 days to 15 years who were linked to having listeriosis.
Walls said this was the first research of its kind in New Zealand to measure the impact and there was still much more work needed to discover the extent of the risks caused by foodborne infection.
In the paper, researchers said there were several factors leading to a lack of food safety knowledge and while healthcare providers were identified as the preferred source of information, difficulty communicating those messages was said to be a problem.
Close to 70 per cent of participants reported receiving information from their midwife, 40 per cent from family or friends, and 33 per cent received advice from GPs.
Other factors highlighted in the study included lack of returning to follow up appointments caused by information overload, underestimated risk due to lack of experiences with food-related illness and convenience of high-risk foods overriding food safety.
"The more awareness we can bring to this issue the better," Walls said.
About foodborne illnesses during pregnancy:
• Babies in mum's tummy are at greater risk of dying from a food infection than the average New Zealander which is why avoiding certain foods is recommended.
• Some foodborne illnesses, such as Listeria and Toxoplasma gondii, can infect the foetus even if the mother does not feel sick.
• If a pregnant mum gets a food infection, it can lead to miscarriage, pre-term delivery or stillbirth.
• While a baby dying from a food infection isn't common, experts say it's preventable if pregnant women stick to The New Zealand Food Safety in Pregnancy guidelines.
• There is limited research available in New Zealand about how many babies die from food infections - we know that between 1997 and 2016, there were 147 pregnancy-associated cases of listeriosis in New Zealand.