With her oversized sunglasses, scrapped back hair and thrown together outfit, Jessica Alba could easily be mistaken for Britney Spears.

The pregnant actress, 26, ditched her usual designer wardrobe for a low-key combination of jeans, sundress and flip-flops - a familiar staple of Spears' wardrobe - for a busy day in Los Angeles.

Alba, who is expecting her first child in June, opted for laid-back comfort as she shopped in West Hollywood, before visiting her doctor.

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Britney-style: The usually stylish Jessica Alba is opting for the Britney Spears 'thrown together' look as she shops in LA

The Sin City star and interior designer Kari Whitman visited several furniture shops together in preparation for decorating her baby's nursery.

After looking for inspiration for her home, Alba visited a medical centre for a pre-natal check-up.

On Sunday, Alba invited celebrity friends Jaime King, Rashida Jones and Kim Kardashian to her baby shower party at the Ever After Teahouse in LA.

During the lunchtime party, a blooming Alba told friends she is expecting a baby girl, People magazine reported.

Alba's fiancé Cash Warren, arrived late at the party to help the actress carry her many gifts to the car.

Among the presents Alba received were prams, cradles and a giant white toy rabbit.

Alba and Warren started dating in autumn 2004 after meeting on the set of the Fantastic Four, where Warren was working as a director's assistant.

The couple were reported to have briefly split last July, but reunited the following month.

They announced Alba's pregnancy and their engagement in December.

Parents-to-be: Jessica Alba and fiance Cash Warren, pictured in New York last month, can't wait to be parents