Los Angeles, Dec 30 : Actress Hilary Duff has reached a new milestone in her pregnancy. The actress, who is expecting her fourth child, revealed on her Instagram Story that she can no longer fit in a pair of her favourite jeans, thanks to her growing belly. She shared a selfie illustrating this, showing her jeans fully unzipped and her belly, reports People magazine. In the photo, the actress closes her eyes and leans against a wall while resting a hand on the top of her baby bump. Her other hand holds her phone up to snap a picture. 'These perfect vintage Levi's carried me through this pregnancy as long as they could,' she wrote over the photo, adding that she needed 'to come for a visit' while tagging clothing store With Love, Lenny. Last week, the 'How I Met Your Father' star shared a sonogram of the child, whom she is expecting with husband Matthew Koma. As per People, the photo showed a closeup of the baby's face in the sonogram, prompting a crack from Duff about its cute features. 'Little stinker with the cute nose,' she captioned the post. Hilary and Koma announced they were expecting another child on her family Christmas card this year, which she also posted to the social media platform. The front of the card displayed a photo of Hilary with her hand on her baby bump as she posed in pyjamas with husband Koma, 36, their children Banks Violet, 5, and Mae James, 2, and her eldest son Luca Cruz, 11, who she shares with ex-husband Mike Comrie. /IANS