Jennifer Lopez was so determined to make sure she was pregnant when she first thought she was with child, she took 20 tests-- and even asked her husband Marc Anthony to pee on a stick.

The actress/singer admits to feeling "a flutter" during a hair and make-up session - and it sent her to the nearest pharmacy.

She tells the upcoming issue of Elle magazine she dashed home with her pregnancy tests in an effort to be sure-- and she even insisted Anthony took one.

She explains, "I needed to see what a negative looked like."

Lopez gave birth to twins Emme and Max on February 22.

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(This news article provided by World Entertainment News Network)