Jury selection is scheduled in federal court in Boston in case involving DES, or diethylstilbestrol. Millions of pregnant women were prescribed the drug between the 1930s and the early 1970s to prevent miscarriages, premature births and other problems.
Drug companies argue that no firm link between DES and breast cancer has been established.
The Melnick sisters say they all developed breast cancer after their mother took DES during pregnancy. They say their mother was not on DES while pregnant with a fifth sister. And that sister has not gotten breast cancer.