Reproductive information on labels slated for revision.

The system that uses letters of the alphabet to categorize drugs' pregnancy and lactation risks will be replaced by a more consistent format designed to be more useful to health care professionals and patients who are of childbearing age, pregnant, or breast-feeding, the Food and Drug Administration announced.

The proposed rule would change the content and the format of the pregnancy and lactation information that is included in the labeling of human drugs and biologics. Under the proposal, the drug label "would explain the potential benefits and risks for the mother, and the developing baby or fetus, and how these risks may change over the course of pregnancy" Dr. Sandra Kweder, deputy director of the FDA's Office of New Drugs, said during a media briefing.

Established in 1979, the current category system uses the letters A, B, C, D, and X to indicate degrees of risk during pregnancy. Many critics in the medical community say the system provides inaccurate and oversimplified information, and that it has caused difficulty in updating labels as new information becomes available.

Under the proposed rule, labels would also include "relevant clinical information to help health care providers make prescribing decisions and counsel women about the use of drugs during pregnancy and/or lactation," according to the FDA. A new pregnancy section would contain three subsections:

* The "Fetal Risk Summary" would summarize known risks of the drug for a fetus and explain whether risks are based on human and/or animal data.

* "Clinical Considerations" would include information about the effects of a drug taken by a woman before she knows she is pregnant.

* "Data" would provide details on the available human and animal data found in the fetal risk summary on the effects of the drug.

The pregnancy section would also contain information about any available pregnancy registries of women exposed to specific drugs.

There would also be a lactation section, which would include the same three subsections used in the pregnancy section.

The section on labor and delivery, which is included in current labels, would be eliminated; this information would be included in the pregnancy section.

Recent studies show that on average, women receive three to five different prescription drugs during pregnancy, she said.

Once the rule is finalized, the new label format would be required for newly approved drugs. Manufacturers of previously approved drugs would be required to comply over a certain number of years or when, for example, another change is made to the label.

More information about the labeling changes is available at www.fda.gov/cder/regulatory/pregnancy_labeling/default.htm.

BY ELIZABETH MECHCATIE

Senior Writer