"The most significant part of the law was the fetal testing section because it appeared to implicate the trimester framework established in Roe v. Wade. This section required that if physicians believed a woman was at least 20 weeks pregnant, before performing an abortion on her, they must first do a series of tests to determine whether the fetus was viable. The lower court ruled that because these tests were costly and potentially dangerous to the woman and the fetus, the provision was unconstitutional. Chief Justice Rehnquist and the other two members of the plurality upheld the law, interpreting it to require physicians to perform the tests only when they believed they would help to determine viability, not in all cases. He acknowledged that the Missouri law was inconsistent with Roe v. Wade by allowing viability tests during the second trimester. But instead of overruling the 1973 decision, the Rehnquist plurality attempted to resolve the conflict between Roe v. Wade and the Missouri law by abandoning the rigid trimester framework. It approved the fetal test provision as a permissible method for the state to further its interest in protecting fetal life, which, in their view, was not simply limited to the third trimester. Conceding that it would allow government regulation of abortion that would have been forbidden under Roe v. Wade, Rehnquist seemed to invite legislatures to pass laws challenging that ruling and indicated that he believed the trimester framework adopted in Roe v. Wade should be modified in future cases."