Testimony set to begin in case claiming link between pregnancy drug and breast cancer

BOSTON - Testimony is set to begin in a federal lawsuit brought by four sisters who believe their breast cancer was caused by a drug their mother took during pregnancy in the 1950s.

The case involves a synthetic estrogen known as DES, prescribed to millions of pregnant women between the late 1930s and early 1970s to prevent miscarriages, premature births and other problems. Studies later showed the drug did not prevent miscarriages.

The Melnick sisters, who grew up in Tresckow, Penn., say they all developed breast cancer in their 40s after their mother took DES while pregnant. They say their mother did not take DES while pregnant with a fifth sister, and that sister has not developed breast cancer. They are seeking unspecified damages.

Opening statements and testimony are expected Tuesday.