KANSAS CITY, Mo. -- Planned Parenthood and the American Civil Liberties Union filed a federal lawsuit Tuesday seeking to stop a Missouri law that bans abortions beyond the eighth week of pregnancy from taking effect Aug. 28.

Lawyers for the ACLU and Planned Parenthood Reproductive Health Services of St. Louis argued in the lawsuit that the bill signed by Gov. Mike Parson in May is unconstitutional. They want the federal court to issue a preliminary injunction and/or a temporary restraining order to stop enforcement of the law until the lawsuit is decided.

The new law is considered one of the most restrictive in the country because it doesn't include exceptions for rape or incest, and would allow the state to charge any provider who performs abortions at or after eight weeks with a felony that could bring a sentence of up to 15 years.

The organizations argue that if the court doesn't stop the law from taking effect their patients will be severely restricted from accessing pre-viability abortions "preventing the vast majority of patients from obtaining the constitutionally protected medical care they seek."

Parson's spokeswoman, Kelli Jones, said the office had no immediate comment. Attorney General Eric Schmitt's spokesman, Chris Nuelle, office didn't immediately return a phone call seeking comment. Parson and Schmidt are among the defendants named in the lawsuit.

If courts don't uphold the eight-week ban, the bill includes a series of less-restrictive bans ranging from 14 weeks up to 20 weeks. The bill also bans abortions based solely on race, sex or a diagnosis indicating the potential for Down syndrome.

Federal law allows states to prohibit abortions after fetuses are viable outside the womb, which can be from 24 to 28 weeks.

Missouri's bill also includes an outright ban on abortions except in cases of medical emergencies, but that would take effect only if Roe v. Wade is overturned.

"We are in the fight of our lives to protect abortion for 1.1 million Missouri women of reproductive age in our state," Dr. Colleen McNicholas, chief medical officer of Planned Parenthood of the St. Louis Region, said in a statement. "The attacks are relentless, but our commitment to our patients' rights and freedoms is unwavering."

Planned Parenthood Reproductive Health Services of St. Louis currently is the only abortion provider in Missouri. The clinic sued state health officials in May, accusing them of using facility licensing rules to close the clinic.

The ACLU also is seeking to collect signatures to put the eight-week ban to a statewide vote in 2020 but Secretary of State Jay Ashcroft has not yet approved the petition. With only a month left until the law takes effect, the organization is running out of time to collect the 100,000 signatures needed to force a referendum.