By Lynn Martinez and Julia Robertson, CPM
During the more than 40 years MotherToBaby affiliates have been serving the public with education regarding exposures during pregnancy, many women have called who are very distressed, sometimes in tears, about finding out they were pregnant while taking a drug categorized as an X or D in the Food and Drug Administration (FDA) system. “I’ve been on birth control pills and I still got pregnant! Does this mean my baby will have birth defects? It’s a category X drug for goodness sake!” This kind of hysterical reaction was, unfortunately, a common call. It was not unusual to even hear that some of these women had contemplated terminations of otherwise wanted pregnancies. The FDA realized that these pregnancy categories were not as helpful as they intended and stopped using them in 2014, about ten years ago. Now they use the Pregnancy and Lactation Labeling Rule (PLLR) that has a narrative summary for medications, similar to what you will find here at MotherToBaby.
But first, a little background…
For decades the FDA had been aware of significant problems with the system used to categorize medications for use in pregnancy. In 1992, the Teratology Society (now known as the Society for Birth Defects Research and Prevention), a group of multidisciplinary scientists who study birth defects, expressed concerns and noted that the Category or ‘CAT’ system led to unnecessary terminations of wanted pregnancies1. The FDA Pregnancy Labeling Initiative recommended elimination of the CAT system, changing the label to include more descriptive risk statements and mandating that drug inserts be updated when human information is known.
Before the labeling rule changed, when a medication was approved for marketing in the U.S., it had to be labeled with one of five pregnancy CATs: A, B, C, D or X. A meant the drug was well-studied and posed no threat to a developing baby; B was a less-studied, but probably still low-risk drug; C was a drug that had not been studied and therefore the risk was unknown; a D-class drug, based on animal or human data, may have posed a risk; and the X classification meant the drug, based on animal or human data, causes birth defects or there was no benefit for its use during pregnancy. Its use was not recommended in pregnancy.
More than 90 percent of new medications were categorized as either CAT C, D or X, the vast majority being C. Drug manufacturers were legally required to update the category if harmful results were reported; however, no such requirement existed for updating the category when studies showed no problems in pregnancy. Most medications on the market in 2014 werelisted as CAT C, when in fact the majority of them should have been labeled as a CAT A or B. Manufacturers knew that no matter a woman’s history, all pregnancies carried a 3 percent risk of having a child with a major birth defect. Because of this, many manufacturers may have felt better protected from lawsuits if their drugs were listed as CAT C, D, or X. So, really, why would they move up medications in those categories up to A or B? They really didn’t have an incentive.
Moving forward and what it means to mom…
With the FDA rule change in 2014, a new set of requirements was put into place to better inform mom. It now requires the manufacturers to ‘upgrade’ a medication’s labeling when studies show the risk has changed. Also, manufacturers will have to explore various ways of discussing in detail the risks associated with the drug. One expert source that manufacturers could consult is a teratogen information service, like MotherToBaby. More information will help you make more informed choices about your health and pregnancy!
There will still be confusion…
As we see the new labels being implemented, there will still be many drugs on the market with the CAT system since it’ll take time to update all of them. MotherToBaby does not recommend the public or providers rely on the old CAT system for risk assessment. We welcome your questions about the system as well as questions about specific medications in pregnancy and breastfeeding for a complete, personalized risk assessment. Please call us toll-FREE at 866-626-6847.
Lynn Martinez is a retired Teratogen Information Specialist. Lynn has traveled around Utah educating doctors, nurse midwives, pharmacists and others over the past three decades.
Julia Robertson, CPM, now retired, works part-time overseeing quality control efforts for MotherToBaby. In her 25-year career as a teratogen information specialist, sheauthored several peer-reviewed publications focusing on maternal medication consumption and the effect on the developing fetus.
MotherToBaby is a service of the international Organization of Teratology Information Specialists (OTIS), a suggested resource by many agencies, including the Centers for Disease Control and Prevention (CDC). If you have questions about medications, alcohol, diseases, vaccines, or other exposures during pregnancy or breastfeeding, call MotherToBaby toll-FREE at 866-626-6847 or browse a library of fact sheets.
- Friedman, J. Teratology 1993:48:506
- For more information go to: http://www.fda.gov/drugs/developmentapprovalprocess/developmentresources/labeling/ucm093307.htm
