Rachel Rebouche in Boston Review:
Though the 1973 decision in Roe established a constitutionally protected right to abortion, it never guaranteed abortion access. The Supreme Court held only that state criminal laws banning abortion were an infringement of the constitutional right to privacy. Patients, in consultation with their physicians, could elect to have an abortion for any reason during the first trimester of pregnancy. In the second trimester states could regulate abortions in order to protect the pregnant person’s health or the dignity of potential life, but after the second trimester, a state was permitted to ban abortion unless terminating the pregnancy was necessary to preserve the patient’s life or health. This trimester system was abandoned in 1992, when the Court held that states could restrict abortion before viability—around twenty-four weeks of gestation—so long as the regulation did not place a “substantial obstacle in the path of a woman seeking an abortion of a nonviable fetus.” The Court’s decision to reject Roe’s trimester framework nevertheless claimed to preserve “the essential holding of Roe.”
More here.