Prescriptions for contraindicated category X drugs in pregnancy among women enrolled in TennCare

Filling of prescriptions for medications labelled as category X by the United States Food and Drug Administration (considered to be contraindicated for use in pregnancy) was identified among 95 284 women enrolled in TennCare, Tennessee's programme for Medicaid enrollees and individuals without health insurance. Using administrative claims data, 391 women (4.10/1000) were identified as having filled category X prescriptions during pregnancy. This included 118 women (1.24/1000) who filled prescriptions for non-contraceptive oestrogens, 81 (0.85/1000) for sedatives, and 71 (0.75/1000) for statins. While many women had physician visits with a diagnosis consistent with a possible indication for an individual drug outside of pregnancy, none of these indications is included for use during pregnancy. Older women and disabled women were more likely than younger women (P < 0.0001) and women enrolled for other reasons (P < 0.0001) to fill category X prescriptions. Nearly two-thirds of the 391 women filled prescriptions after clinical signs or pregnancy tests would indicate pregnancy; nearly 40% filled a category X prescription after a pregnancy-related physician visit. Although the absolute rate of category X medication use in pregnancy is low, substantial numbers of women and their fetuses are exposed during pregnancy. Women above the age of 35 years and women enrolled in TennCare because of disabilities were more likely to fill prescriptions for category X medications during pregnancy than others, implying that risk communication to practitioners and women should focus on identification of these women to reduce their risk of exposure.