<text>  She may be seven months pregnant and mother to a toddler, but one look at the Duchess of Cambridges flawless skin and you would never guess it. So whats the secret behind the 33-year-olds pregnancy glow? An all-natural rosehip oil, apparently. According to US Weekly, Kate has been slathering Trilogys Rosehip Oil onto her skin while carrying the second royal baby. Scroll down for video . The Duchess of Cambridge, who is seven months pregnant with her second child, is said to be a fan of Trilogys 16.50 rosehip oil . Kate is very cautious of products and treatments, a source told the magazine. Babys health comes first. Kate continues to use rosehip oil in her daily skincare regiment. She loves the effect is has on her skin. Her mother Carole Middleton is also a fan. The oils description reads: Rosehip oils potent natural actives make it highly effective for a variety of skin concerns including dehydrated and ageing skin. Trilogys rosehip expertise ensures the finest quality oil with minimum 80 per cent essential fatty acids omega 3 and 6 and fatty acid omega 9 content. Independent clinical studies show it helps improve the appearance of scars, stretchmarks, fine lines and wrinkles. A source told the magazine: Kate continues to use rosehip oil in her daily skincare regiment. She loves the effect is has on her skin. Her mother Carole Middleton is also a fan Derived from the wild rose bushes that grow high in the Chilean Andes, where the altitude and pollutant-free environment produce the highest quality rosehips, the oils benefits have been known by the indigenous population for hundreds of years. Not only is it rich in vitamin C and high in omega 3 and 6 fatty acids, known to heal scar tissue, its also a great source of retinoic acid, which studies show reduces the appearance of wrinkles and brightens skin. As with anything that Kate is reported to be a fan of, the 16.50 oil has already sold out online at Boots.com. It has also been reported that Deborah Mitchell uses Rosehip Oil in her LIA therapy treatment that Kate loves. The Kate effect strikes again? The oil has already sold out on Boots.com . Models David Gandy, right, and Miranda Kerr have also praised the oils skin-boosting properties . It is results like these that prompted Kate Middletons facialist, Deborah Mitchell, to add rosehip oil to her signature LIA therapy treatment. Rosehip is perfect for all ages and skin types, including those with sensitive skin conditions like rosacea and acne. I add a drop to moisturiser to boost the results - Kate loves it because it gives skin a luminous glow, Deborah told the Daily Mail back in 2012. Models David Gandy and Miranda Kerr have also praised the oil. I put it on at night and I wake up glowing, Miranda has said. The model loves it so much that she even created her own version for her Kora Organics skincare line. A spokesperson for the Duchess of Cambridge declined to comment when contacted by MailOnline. Many brands are using the wonder ingredient in their products. L-R KORA Organics by Miranda Kerr - Luxurious Rosehip Body Oil, 45, Pai Rosehip BioRegenerate, 22, Neals Yard Remedies Rehydrating Rose Facial Oil, 20 . 