From the summary of Abortion: Judicial History and Legislative Response (RL33467, Dec. 7, 2018):
In 1973, the U.S. Supreme Court concluded in Roe v. Wade that the U.S. Constitution protects a woman’s decision to terminate her pregnancy. In a companion decision, Doe v. Bolton, the Court found that a state may not unduly burden the exercise of that fundamental right with regulations that prohibit or substantially limit access to the procedure. Rather than settle the issue, the Court’s rulings since Roe and Doe have continued to generated debate and have precipitated a variety of governmental actions at the national, state, and local levels designed either to nullify the rulings or limit their effect. These governmental regulations have, in turn, spawned further litigation in which resulting judicial refinements in the law have been no more successful in dampening the controversy.