The star quickly tweeted about the incident, revealing her penchant for a restorative ham and cheese toastie: @lilyrosecoopoer "Just fainted in Harrods. #croquemonsieur needed."
Out buying festive treats for her growing family, Allen soon managed to pick herself up and was back on the shopping case, tweeting: "On the bright side, managed to pick up Professor Snape Wand in Ollivanders box and Slitherin pen for Nephews Xmas present.#luckyboy"
Fainting, although it can feel scary, is a common complaint amongst pregnant women due to the hormonal changes happening in the body. Don't miss our guide to fainting in pregnancy for tips and reassurance.
Allen is pregnant with her second child with husband Sam Cooper. The pair are also looking forward to daughter Ethel's first birthday, this Sunday.
MFM wonders if she was also doing a spot of birthday present shopping, too?
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