Documentation of contraception and pregnancy when prescribing potentially teratogenic medications for reproductive-age women.

BACKGROUND

Certain medications are identified by the U.S. Food and Drug Administration (FDA) as class D or X because they increase the risk for birth defects if used during pregnancy.

OBJECTIVE

To assess pregnancy rates and the frequency of contraceptive counseling documented with prescriptions for class D or X drugs filled by women of reproductive age.

DESIGN

Description of prescriptions filled in 2001.

SETTING

A large health maintenance organization in northern California in 2001.

PATIENTS

488,175 women age 15 to 44 years who filled a total of 1,011,658 class A, B, D, or X prescriptions.

MEASUREMENTS

Medications dispensed, contraceptive counseling, and pregnancy testing.

RESULTS

A class D or X prescription was filled by 1 of every 6 women studied. Women who filled a prescription for class D or X medications were no more likely than women who filled prescriptions for safer, class A or B medications to have received contraceptive counseling, filled a contraceptive prescription, or been sterilized (48% vs. 51% of prescriptions). There was little variation by clinical indication in rates of contraceptive counseling with class D or X prescriptions, except for isotretinoin. Women who filled a class D or X prescription were only slightly less likely to have a pregnancy documented within 3 months than women filling a class A or B prescription (1.0% vs. 1.4% of prescriptions).

LIMITATIONS

International Classification of Diseases, Ninth Revision, codes underestimate contraceptive counseling. Documentation of a positive pregnancy test after filling a prescription may overestimate medication use in early pregnancy. Women who filled several prescriptions are overrepresented in prescription analyses.

CONCLUSION

Prescriptions for potentially teratogenic medications are frequently filled by women of childbearing age without documentation of contraceptive counseling.