The recent US Supreme Court decision in Planned Parenthood v Casey, by changing the legal standard by which restrictions on abortion are evaluated, will have a profound effect on access to reproductive health care in the United States. This article reviews the Pennsylvania antiabortion restrictions at issue in Casey and discusses the ways in which the new constitutional standard fundamentally weakens the legal protections previously afforded women and physicians in the 1973 case, Roe v Wade. While the majority opinion reaffirmed a woman's right to choose an abortion, the opinion opens the door to a multitude of new restrictive abortion laws, which diminish, and in some cases completely block, a woman's ability to exercise that right. The effect of weakened legal protection will fall most heavily on young, poor, minority, and rural women, who will be unable to overcome obstacles imposed by mandatory waiting periods, biased counseling, and parental notification requirements. The restrictions are also likely to exacerbate the shortage of physicians providing abortion services by making the procedure more costly and the providers' jobs more dangerous. Finally, the medical community can help to ensure women access to comprehensive and competent reproductive health care.