"The most impressive attempts to anchor the right to abortion in the Constitution’s text have been built on the equal protection clause of the fourteenth amendment. These have argued that the real issue in the abortion controversy is not privacy, but the equality of women Sylvia Law has shown how sex equality concerns are implicated when laws outlawing abortion “impose upon women burdens of unwanted pregnancy that men do not bear,” and correctly observed that “[n]othing the Supreme Court has ever done has been more concretely important for women than its decision in Roe.” The difficulties of this argument stem from the indeterminacy of sex discrimination doctrine: the Court has never made clear what the “intermediate scrutiny” to which sex-based classifications are subject amounts to, so it is difficult for a defense of abortion that relies upon it to secure enough doctrinal traction to get where it wants to go."