The pop star - who is expecting her first child with boyfriend Sam Cooper - admits the couple have no plans to tie the knot just yet but she has told her partner she would like to make their union official in future.
Lily - who is due to give birth in February - revealed she is still getting used to her pregnancy and the fact that people freely comment on her changing body shape.
She said: "The weird thing about being pregnant is that it seems to give people the license to talk about your body shape and say things like `Wow you have got so big!`. Thanks, I always say, `I`m embracing it.` "
Lily`s sister Sarah Owen - with whom she has recently opened vintage clothing shop Lucy in Disguise - claimed that men are loving her sister`s new body shape.
She said: "Men can`t get enough of it. It`s true. Especially older men."
The `Not Fair` hitmaker has regularly hit the spotlight over her fluctuating weight and she admits her shape changes depending on her state of mind.
She added to the Daily Telegraph website: "In the end my size has always been to do with my general state of mind. If I`m feeling good about my work and everything else in my life, I could be seventeen stone and still feel beautiful.
"But when I`ve felt really tired, low and lacking in confidence I could feel sick looking at myself in the mirror. I`ve got this sticking out stomach but I`ve looked in the mirror and thought it was fine."