Coco Rocha carefully conceals her baby bump in a high-waisted skirt at charity event in New York

She revealed last month that she is expecting her first child.

And although supermodel Coco Rocha did so by posting a video of her bump, it seems she isn't quite ready to show it off on the red carpet.

The 26-year-old attended the the K.I.D.S./Fashion Delivers Annual Gala in New York on Wednesday, and kept the bump carefully concealed in a high-waisted skirt.

Joining Coco at the event, was fellow supermodel Heidi Klum, who looked classy in a cream gown.

Coco announced her happy news by releasing a joint statement with her artist husband James Conran.

She revealed on Instagram: 'We are absolutely thrilled and elated to announce that after four years of marriage we are expanding our family and expecting our first child spring of 2015!'.

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Strangely, the model released a short video of herself to reveal the news - featuring herself dressed in a nude ballerina dress.

As a music box-style tune is played, the camera pans around Coco, with husband James looking on in the background, eventually the camera zooms in on her stomach area when the message appears 'Baby Conran arriving Spring 2015'.

Coco - who married James back in 2010 - recently revealed to People that her mother Rocky does not want to be known as a grandmother.

'They have to call her by her first name,' she told the publication last year.

Adding: 'I think this is a new thing, women not wanting to be called grandma.'

Coco married when she was 22, and in 2012 she revealed it would 'unfair' to have a child while she was busy with her modelling career.

'Right now it would be unfair to have a kid in the mess of all my life,' she said. 'But when my work is done, I would love to have kids with James.'

In the same interview - for FASHION magazine - she also spoke about her religious beliefs, and regrets over certain modelling jobs.

She said: 'At the beginning of my career there were photos and moments I wish I wasn’t a part of but I didn’t realize I could say "no."'

'Now I know that. I grew up - and still am - a practicing Jehovah’s Witness and believe in everything the Bible has to say. I’m a Christian first and a model second.'

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