Jessica Simpson -- Takin' My Fetus to Target

Just two days before she made her big announcement, a secretly pregnant Jessica Simpson took her fetus on a Christmas Eve shopping spree ... and showed off her growing baby bump.

While wearing an animal print tunic-thingy, Jessica hit up a Target store in Hawaii on Sunday to stock up on wrapping paper and all sorts of other competitively priced stuff.

It's unclear how far along she is, but it's gotta be early ... considering you can BARELY see the bulge in her midsection.

Side Note: Her legs look great!