Children's clothing company The Gymboree Corporation has posted a seven per cent drop in net sales for the four-week period ending November 1, based on the same period in 2002.

The Californian company recorded sales of $48.7 million for the four weeks, down from $52.6m a year earlier.

Chairperson and CEO Lisa Harper blamed Gymboree's lack of product differentiation from its competitors for the slump.

"We are confident that our ongoing product strategy will maintain our position as a market leader in terms of fashion and novelty merchandise," she said.

Net sales from retail operations, meanwhile, were up four per cent to $394.6m for the 39 weeks to November 1, compared to the same period last year.

Gymboree operates 612 namesake retail stores throughout North America and Europe, as well as 25 Janie and Jack outlets in the US.