Washington (CNN) Rep. Alexandria Ocasio-Cortez on Wednesday sharply criticized a new Georgia abortion law, calling it a "backdoor ban."

Georgia Republican Gov. Brian Kemp on Tuesday signed a controversial bill that would ban abortions if a fetal heartbeat can be detected, which can be as early as six weeks into a pregnancy -- when many women don't yet know they are pregnant.

Ocasio-Cortez, a freshman New York Democrat, posted on Twitter , "'6 weeks pregnant' = 2 weeks late on your period."

"Most of the men writing these bills don't know the first thing about a woman's body outside of the things they want from it," Ocasio-Cortez wrote. "It's relatively common for a woman to have a late period + not be pregnant."

"So this is a backdoor ban," Ocasio-Cortez wrote.

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