Sienna Miller (WENN.com)

British artist Jonathan Yeo has unveiled a nude portrait of actress Sienna Miller during her pregnancy.

The Alfie star gave birth to her baby daughter Marlowe in July, and she decided to document her journey to parenthood by stripping off for Yeo weeks before her due date for inclusion in his upcoming (I've Got You) Under My Skin exhibition in Berlin, Germany.

In a catalogue for the exhibition, Yeo states, "I wanted an image that epitomized the human body in its most naturally beautiful state to make the sharpest possible contrast with my other paintings in this exhibition, which document patients undergoing cosmetic surgery in a bid to help them conform to societal notions of beauty..."

Yeo admits he wanted the naked painting to become a talking point to help break down barriers in society, just like Demi Moore's nude and pregnant Vanity Fair cover photo did in 1991.

He continues, "It has been 22 years since a pregnant Demi Moore caused uproar by posing for Annie Leibovitz on the cover of Vanity Fair. In that time society has become almost completely desensitized to the daily exposure to people who have surgically distorted their appearance for artificial reasons.

"Yet certain sections of society are still uncomfortable with the appearance of pregnancy and images of naked expectant mothers are rarely seen."

The artist states it made sense for him to debut the image, which he has posted on his website, in Germany, because it's a country "with a very relaxed attitude to nudity, where it is not automatically sexualized or deemed scandalous".

He adds, "The power of the painting partly lies in the fact that Sienna is widely regarded as being one of the most naturally beautiful actresses in the world, as well as being a fashion icon to a generation of girls.

"It is a tribute to her courage and self-confidence that she agreed to sit for this. I can think of many figures whose public currency in part revolves around their appearance, who would prefer to hide themselves away for nine months."

Yeo, the son of former Conservative Minister Tim Yeo, previously captured Miller on canvas in 2010.

Sienna Miller poses for a portrait by Jonathan Yeo.