Supreme Court 5-4 reaffirms Roe's core holding in Casey but abandons the trimester framework, replacing it with an 'undue burden' standard and upholding most Pennsylvania restrictions

The Supreme Court ruled 5-4 on June 29, 1992, that states may not place an undue burden on the right to abortion before fetal viability. An unusual joint plurality opinion by Justices O'Connor, Kennedy, and Souter reaffirmed Roe's core holding — that the Constitution protects the liberty to choose abortion — while discarding Blackmun's trimester framework in favor of a viability-based "undue burden" standard. The plurality upheld Pennsylvania's 24-hour waiting period, informed consent, and parental consent requirements, but struck down the spousal notification provision as an undue burden. Four justices (Rehnquist, Scalia, White, Thomas) would have overruled Roe entirely. Blackmun and Stevens would have affirmed strict scrutiny.