The 37-year-old fashion designer debuted her spring/summer 2012 line at New York Fashion Week and said her eight-week-old daughter Harper has helped her with her busy schedule.
She said: 'I've had to develop a very strategic way of working. But Harper has also done her bit. She's so well behaved.'
But Beckham, whose three sons remained in Los Angeles with their dad David, said she had to leave Harper behind for the event.
Speaking to UK newspaper The Daily Telegraph, she said: 'It's the first time we've been separated. I just want her with me all the time. But it would have been too noisy for her at the show.'