In Reproductive Health Services of Planned Parenthood of St. Louis Region v. Parson, Nos. 19-2882, 19-3134, — F.3d —-, 2021 WL 2345256 (8th Cir. June 9, 2021), a divided Eighth Circuit panel upheld a district court decision to preliminarily enjoin enforcement of two provisions of a Missouri abortion law that once again tested the distinction between outright bans on certain pre-viability abortions—which are categorically prohibited under the Supreme Court's decision in Planned Parenthood of Southeast Pennsylvania v. Casey, 505 U.S. 833 (1992)—and regulations that impose conditions on, but do not prohibit, pre-viability abortions.

The "Gestational Age Provision" of Missouri's House Bill 126 is actually a series of statutes that subject to criminal prosecution and professional discipline any provider who performs an abortion at or after 8, 14, 18, and 20 weeks of fetal gestational age "except in cases of medical emergency." The "Down Syndrome Provision" of HB 126 imposes civil penalties on any provider who performs an abortion when he or she "knows that the woman is seeking the abortion solely because of a prenatal diagnosis, test, or screening indicating Down [s]yndrome or the potential of Down [s]yndrome in an unborn child."

In July 2019 Reproductive Health Services of Planned Parenthood of St. Louis Region (RHS) sued Missouri on behalf itself and prospective patients and sought an injunction to stop both provisions from going into effect, arguing that they are bans that are unconstitutional under Casey. The District Court for the Western District of Missouri initially preliminarily enjoined only the Gestational Age Provision, finding that RHS had not presented evidence showing that, in the absence of an injunction, an abortion due to a diagnosis of Down syndrome would actually be prevented before a final judgment could issue. After RHS presented additional evidence in the form of a declaration from Dr. Colleen McNicholas, RHS's Chief Medical Officer, the district court also preliminarily enjoined the Down Syndrome Provision. Missouri's separate appeals of the two injunctions were combined in the Eighth Circuit.