The lack of oversight has been exposed as a rising number of Sydney parents are choosing wheeled trailers, wheelbarrow-style cargo boxes, front-mounted baby seats and bucket bikes for family transport.

Their popularity has prompted an independent review of their safety, which is expected to be open for public comment by the end of the year.

The current Standards Australia guidelines - which only cover baby seats behind the rider - require carriers to have five harness points and strapped foot rests and that the child weigh less than 22 kilograms.

''The last review done was in 1995 and most of these products weren't available,'' said Peter Bourke, general manager of Bicycle Industries Australia. ''But most of the trailers are made overseas and are designed to meet European standards. The vast majority are extremely safe.''

He said changes to technology, new trends and awareness of injury data had sparked the review to ''ensure we have the safest child bike seats available''.

''There are products like trailers on the market, which have never been tested for safety in Australia.''

The incidence of injury from using carrier seats is small. Transport for NSW's Centre for Road Safety has reported only nine bicycle passenger injuries in children aged under 10 between 2008 and 2012.

City of Sydney's cycling strategy manager, Fiona Campbell, said the ''massive increase'' in the use of baby bike seats, particularly in Chippendale and Newtown, was largely because it was a practical way of ferrying children on short trips to school and daycare.

''Bikes are reliable and flexible,'' she said. ''I've never heard of anyone having a safety issue.''

In the past three years, the number of people cycling through central Sydney had more than doubled, Ms Campbell said, with the strongest growth in Newtown and Darlington. About 2000 riders passed through each of the city's main intersections each day.

Recent tests by consumer group Choice have reinforced the need for a safety review, with some available products not meeting the current standard.

At Newtown's Cheeky Transport, manager Donald Graham said sales of child bike seats had risen by about 30 per cent in the past five years, with parents increasingly buying chairs for for babies less than six months old.

''There is a real eagerness for them to get them on a bike,'' he said. ''But, if they are too small to fit into a helmet and can't sit up properly, they have to wait.''

Standards Australia's new safety guidelines are expected to be published in 2015.

More cyclists are attaching baby seats to their bicycles

Every weekend Nicole Naunton clips her two-year-old son, Sebastian, on the back of her Dutch-style bicycle and spins over the headland from Freshwater to Manly.

''Riding is so much more entertaining for him than sitting in the back of a car looking at a headrest,'' says the 38-year-old, who regularly shuttles her extra cargo along Sydney's inner-city roads and cycle paths.

Ms Naunton is not alone. She is among hundreds of urban cyclists who are ditching their cars for bikes as one of the main modes of family transport.

Ms Naunton, whose son made his cycling debut at nine months in a front-mounted seat, now uses a rear suspension seat which, she says, is more visible to motorists.

''The experience of riding with a child compared to riding alone is really different,'' she says. ''People give us a wide berth, they slow down and are more courteous.

''It's a way to get some exercise and being on child-minding duty at the same time.''