The 29-year-old mum-of-two apparently bought the pill, along with a selection of condoms, pregnancy tests and other items for a friend's birthday.
She then posed for a picture of herself surrounded by the products which was posted to Instagram by her friend, musician Benjamin Garrett, who sings under the name Fryars, and then re-posted by Lily.
Benjamin wrote: "Birthday gifts from @lilyallen who had to pretend she'd had unprotected sex to get me a morning after pill."
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