Estrogens classified as carcinogens

Sex hormones of the class known as steroidal estrogens, which are in hormone-replacement therapies and birth control pills, are among the latest compounds that a government panel of U.S. scientists has recognized as cancer agents in people.

The National Institutes of Health in Bethesda, Md., periodically reviews cancer-research literature and updates its list of known or suspected human carcinogens, which now number 228.