Lego's controversial courting of the girls' toy market has paid off for the Danish company after it announced a 35% increase in first-half profits.

The world-famous plastic brick maker said net profit rose to 2bn kroner (£213m) in the first six months of 2012, from 1.48bn kroner for the same period last year. Sales rose 24% to 9.1bn kroner, spurred by the success of the Lego Friends line, which launched in January in an attempt to expand the company's appeal beyond boys and has been a runaway hit, selling twice as many sets as expected.

"It has been amazing to experience the enthusiastic welcome that consumers have given the new range," said the Lego chief executive, Jørgen Vig Knudstorp. "Sales have been quite astonishing."

The debut of Lego Friends, featuring a more prominent use of pink than your typical Lego fan would be used to, drew criticism from some consumer groups who said it would reinforce gender stereotypes. As well as the usual trucks, policemen and rugged houses, the line now includes "Stephanie's cool convertible" in distinctive pink and purple, and "Mia's Puppy House", accessorised with flowers and full pet grooming kit.

The loudest protest against the range came from the US, where the Spark movement against the sexualisation of girls and young women organised a petition with more than 50,000 signatures calling on Lego to change its marketing strategy. Eating disorder specialists have also criticised the line, which has slim figurines called Stephanie, Andrea and Olivia who represent a significant change to Lego's typical square-set characters.

However, Lego's results indicated that the company had got its product design and marketing right, having drawn up the new line amid requests from parents and girls for more realistic and detailed sets with brighter colours and role playing opportunities.

"With Lego Friends we've managed to make creative construction toys more relevant for girls – and we look forward to developing the product line further in the years ahead," said Knudstorp. Lego said a weakening toy market had not damaged the privately-owned business, with its share of the global toy market growing by one percentage point to more than 8%. European sales rose by 10%, Lego said, with the US climbing 23% and Asia increasing "at an even steeper rate". The company expects to hire an extra 1,000 employees this year – a 10% boost to its workforce – as it meets growing demand, including increased production of the Friends line. However, Lego City and Lego Star Wars remain the group's biggest selling products.

© Guardian News and Media 2012

[Lego friends via LostCarPark / Flickr]