Missouri's Republican-led House has passed sweeping legislation designed to survive court challenges, which would ban abortions at eight weeks of pregnancy.
If enacted, the ban would be among the most restrictive in the US.
It includes exceptions for medical emergencies, but not for pregnancies caused by rape or incest.
Doctors would face five to 15 years in prison for violating the eight-week cut-off. Women who receive abortions wouldn't be prosecuted.
Republican Governor Mike Parson pledged to sign the bill , but it's unclear when he'll take action. When pressed on the lack of exceptions for rape or incest, he told reporters that "all life has value".
"I'm going to stand up for the people that don't have a voice," Parson said.
"Everybody should have a right to life."
The Missouri legislation comes after Alabama's governor signed a bill on Wednesday making performing an abortion a felony in nearly all cases.
Supporters say the Alabama bill is meant to conflict with the 1973 Roe v. Wade decision that legalised abortion nationally in hopes of sparking a court case that might prompt the current panel of more conservative justices to revisit abortion rights.
If courts don't allow Missouri's proposed eight-week ban to take effect, the bill includes a ladder of less-restrictive time limits that would prohibit abortions at 14, 18 or 20 weeks or pregnancy.
© AP 2019