Parents are losing hundreds of dollars through fraudulent websites claiming to sell popular baby products.
And even those who get something for their money may be putting their children at risk, experts say.
In recent months there has been a sharp increase in the number of sites offering big-name items such as Ergobaby carriers, which can retail for more than $200 in shops.
The sites use pictures and text taken from legitimate retailers. But when an order is placed, buyers either receive a counterfeit product or nothing at all.
Netsafe operations manager Lee Chisholm said it was a growing problem. "There are the websites which trade in counterfeit goods claiming to be originals, websites which never send goods after payment is made, and Facebook pages where people advertise and again never send the goods after payment has been made."
Rochelle Gribble, of parenting website Kiwi Families, said there were safety issues relating to the material used in the carriers, the strength of the fabric and the way the products were stitched.
Auckland mother-to-be Charley Monger was caught out by one of the sites last week. She spent $160 on what she thought was an Ergobaby carrier before discovering that the website was fake. She contacted her bank, which advised her to cancel her debit card but the money had already been taken. "I've shopped on the internet for years and it didn't occur to me."
Monger said it was distressing to have lost money as she prepared for her first baby, due in June. "It's annoying but I've had to think, well, if you go out for a night out and have a nice meal and a few drinks, you'd spend that amount. It's not the end of the world but it's a pain."
She was told to cancel the card as some sites retain the details.
Auckland woman Rebecca Payne also placed an order with the fake site. "The bank was quite good and said it happens a lot and I need to go through a process for them to investigate."
Louisa Currie, of baby product retailer Belly Beyond, said there were hundreds of counterfeit baby carriers in the country and it was a serious safety concern. She had noticed an increase in the fake sites since August. Because they were based overseas, little could be done.
"We've just had a third person since Christmas call to say the buckle has broken. They don't stack up from a quality perspective. If the buckle breaks, the baby can fall.
"There's not a huge amount we can do except educate people that if it looks too good to be true."