Rosie Huntington-Whiteley takes 100 photos before she finds the perfect selfie.

The 30-year-old model - who is expecting her first child with fiance Jason Statham - insists it takes her a lot of time, effort, and digital changes to create the right image to post on her social media accounts, but hopes that doesn't make her ''obnoxious''.

Asked how to take the perfect selfie, she said: ''Well, you need half an hour, you need great lighting, and you need to be prepared to take about 100 pictures of yourself, edit through 100 pictures of yourself and then filter them three times.'

''You know, come on! Be real! That's the way it is.

''I try to be mindful of that when I'm posting pictures, but again, it's part of what I do and I hope that people don't feel...that my social media is too obnoxious.''

And Rosie admitted she worries about the impact of perfect Instagram pictures on ''insecure'' young girls as even she is given to feeling uncomfortable about herself when she sees flawless images.

She added to the upcoming new issue of Britain's Glamour magazine: ''[I worry about] young girls out there who are really feeling insecure about their image and they scroll through and see this image of a supermodel looking amazing, reclining on the beach in a completely unrealistic pose or environment.

''And I can see how that would make people not feel good about themselves. I mean, I can't say that I'm immune to that. Sometimes I'm like, 'F**k!' You know? That doesn't make me feel great.''

The British beauty lives in Los Angeles with her 49-year-old partner but admitted she gets very ''homesick'' for her native UK.

She said: ''Oh my God. I miss everything about home. I get homesick a lot... I miss the culture. I miss the people and I miss the realness of Brits and the sense of humour.''