Parents are being told to avoid using talcum powder on their babies because of suggested links to cancer.
Childbirth educator Sandy Chris warns women who attend her antenatal classes that they should not use the product at all after studies showed its use was linked to an increased risk of ovarian cancer.
"I just want to raise awareness about it ... parents just don't seem to know about it," Mrs Chris said. "The knowledge of it is just put aside."
A Harvard Medical School study in 2008 found women who used talcum powder every day on their genital areas were 40 per cent more likely to develop ovarian cancer. Used once a week, the risk was 36 per cent.
Experts analysed data from more than 3000 women collated in two studies.
However, the findings, published in the journal Cancer Epidemiology, Biomarkers and Prevention, apply only to talc used around the private parts, and did not involve babies. But they echo evidence in a number of other studies which suggest a link to higher cancer risks.
The British NHS said: "Although this study has shortcomings and does not provide strong evidence of a causal link in itself, when put in context with other studies on this topic, it adds to the body of evidence suggesting that use of talc may be linked to ovarian cancer."
Dr Jan Pearson, health promotion manager at the Cancer Society of New Zealand, said with the way the studies were conducted it was difficult to know for sure.
"Unless it's a controlled trial to know how much talcum powder they've used and where they've put it and all those types of things, what tends to happen is that they end up with a correlation, a link, but it's not normally cause and effect," she said.
The risk of women developing ovarian cancer in their lifetime was 1.4 per cent, so even if there was a 30 per cent increase the lifetime risk was still very low, Dr Pearson said. "If you are concerned, don't use it."
Parents could use other products, such as baby powder, creams or cornflour if they needed to dry their infant.
Director of the Kiwi Families websites, Rochelle Gribble, said talcum powder's possible link to cancer seemed to be quite well known by new mothers.
A spokeswoman for Plunket said they were not aware of the link.
A Countdown spokeswoman said there were no warnings about talc online at the Ministry of Health, New Zealand Cancer Society or Plunket.
Alison Goodall, marketing manager at Church & Dwight, said the company's Curash Anti-Rash Baby Powder was approved by monitoring agencies in the US, Australia and by Medsafe in New Zealand.
"Since 1973 talcum powders have been required by law to be asbestos free. Talc is now considered to be safe for use on the external genitals," she said.
KIDS GET A COATING OF CORNFLOUR
Olivia Wallbank chose not to use talcum powder on her children because of its possible ties to ovarian cancer - even though she had two boys.
The Hamilton mother of Chaz, 3, and Zak, 16 months, found cornflour was just as effective and it was natural so she knew there wasn't any risk if they inhaled it.
"I just figured I always had cornflour in the cupboard, so I may as well use that," she said.
"I don't know if it worked just as well because I've never used talcum powder, but it sure worked on their little creases."
Mrs Wallbank thought it was better to be safe than sorry.