Missouri's Republican-led House passed a bill banning abortions at eight weeks of pregnancy with an exception for medical emergencies but not for rape or incest.
"Until the day that we no longer have abortions in this country, I will never waiver in the fight for life," Parson said during a rally Wednesday.
Under the bill, which passed in the House by 110 to 44, doctors who perform an abortion after the eight-week cutoff could face five to 15 years in prison. Women who receive abortions would not be criminally penalized.
Missouri's Republican-led Senate passed that state's bill, called Missouri Stands With the Unborn, by a vote of 24-10 on Thursday morning.
Once enacted, the law will only kick in if Roe v. Wade is overturned, and Planned Parenthood was assuring women in the state that facilities that provide abortions are still open in Missouri and neighboring Illinois.
"Gov. Parson is willfully aiding in the systematic downturn of health outcomes across our state, and banning safe, legal abortion is just the latest effort," said MEvie Mead, the director of Planned Parenthood Advocates of Missouri in a statement. "Shame on him for suggesting the government should have a say in when and whether someone becomes a parent."
Anti-abortion advocates across the U.S. are pushing for new restrictions on the procedure in hopes that the now more-conservative U.S. Supreme Court will overturn more than 40 years of federal abortion protection under Roe v. Wade.
The bill's sponsor, Rep. Nicholas B. Schroer, said Friday that the purpose of the bill wasn't to provoke court challenges.
"This legislation has one goal, and that is to save lives ... to withstand judicial challenges and not cause them," he said.
If the courts block the eight-week ban, the bill has built-in concessions of less-restrictive time limits that would prohibit abortions at 14, 18 or 20 weeks or pregnancy.
In the past two weeks, both Alabama and Georgia have passed strict abortion laws, although they have not yet taken effect, and may never be implemented, depending on results of court challenges.
Alabama's law, signed by Gov. Kay Ivey on Wednesday, makes it a felony for a doctor to perform or attempt an abortion during any stage of pregnancy.
The state's House approved the bill with an exception for cases when a mother's health is at serious risk. The Senate considered but rejected also adding exemptions for when the pregnancy results from rape and incest.
The law is not due to go into effect for six months after the signing. Under current law, abortions can be performed up to 21 weeks and six days. As it is, there are only three abortion clinics left in the state of Alabama.
Georgia's law, signed by Gov. Brian Kemp, bans abortions once a fetal heartbeat can be detected which can happen as early as six weeks, before many woman are aware they are pregnant.
The law includes rape and incest exceptions, if the woman filed a police report. It also includes exceptions to save the mother's life and if a fetus is determined to not be viable because of serious medical issues.
Under current law, abortions can be performed during the first 20 weeks of a pregnancy. The new ban is not due to go into effect until Jan. 1, 2020.
Kentucky, Mississippi and Ohio have also approved bans on abortion once fetal cardiac activity can be detected. Some of those laws already have been challenged in court, and similar restrictions in North Dakota and Iowa previously were struck down by judges.