DES MOINES, Iowa (AP) — Legislators in the Republican-controlled Iowa House have begun debate on a so-called “heartbeat” bill that seeks to ban most abortions in the state. Lawmakers are expected to debate for hours Wednesday over the legislation, which would ban most abortions once a fetal heartbeat is detected. That’s usually around six weeks of pregnancy.

The measure would need a final vote in the GOP-led Senate before it can be sent to Republican Gov. Kim Reynolds, who hasn’t said whether she’d sign it into law. If enacted, the legislation would almost certainly be challenged over whether it violates U.S. Supreme Court rulings.

Mississippi passed a law earlier this year that bans abortion after 15 weeks of pregnancy. That legislation is considered the nation’s most restrictive abortion law, but it’s on hold amid litigation.