Am Fam Physician. 2003;67(4):700-701
to the editor: The article by Dr. Brundage, “Preconception Health Care,”1 also stresses the importance of postconception counseling because “40 to 50 percent of pregnancies are unintended,” according to the article. Post-conception counseling for inadvertent exposure to medications is therefore just as important as preconception counseling.
Drug labeling is one source of information; however, it is usually outdated regarding teratogenic risks. Multiple other sources are available to assist physicians in assessing reproductive toxicities from drug exposures. The online REPRORISK system (available from Micromedex) contains electronic versions of four teratogen information databases: REPROTEXT, REPROTOX, Shepard's Catalog,2 and TERIS.3 These resources are updated and scientifically reviewed and provide a critical evaluation of the literature regarding human and animal pregnancy drug exposures. More than 20 comprehensive multidisciplinary Teratogen Information Services (TIS) are located in the United States and Canada, that provide patient counseling and risk assessments regarding potential teratogenic exposures (www.otispregnancy.org). Many TIS, such as MotherRisk (www.motherisk.org), use genetic counselors who are excellent resources for pre- and postconception counseling. The National Society of Genetic Counselors (www.nsgc.org) also can locate genetic counselors in most geographic regions.
Erroneous information about drug-associated teratogenic risks is prevalent and can result in unwarranted anxiety along with unnecessary health care interventions, including elective termination of wanted pregnancies.4 Brundage1 erroneously reports that angiotensin-converting enzyme (ACE) inhibitors and angiotensin-II receptor antagonists are pregnancy risk Category D. In fact, they are pregnancy risk Category C for first trimester and category D for the second- and third-trimester exposures. The package insert states: “When used in pregnancy during the second and third trimesters, ACE inhibitors can cause injury and even death to the developing fetus … Female patients of child-bearing age should be told about the consequences of second- and third-trimester exposure to ACE inhibitors, and they should also be told that these consequences do not appear to have resulted from intrauterine ACE-inhibitor exposure that has been limited to the first trimester.” Although these drugs should be discontinued on confirmation of pregnancy, Table 2 of the article1 unfortunately reinforces misleading information that can be alarming to a pregnant woman who is inadvertently exposed during the first trimester.
The U.S. Food and Drug Administration (FDA) recognizes that the availability of factual information is imperative to providing good health care for pregnant women. Unfortunately, package inserts for drugs do not always provide up-to-date information regarding risks during pregnancy. For example, recent research5 provides evidence, not cited in labeling, that the increased risk of congenital anomalies in children of mothers with epilepsy is associated with the use of anticonvulsant drugs in pregnancy, rather than with epilepsy itself. The FDA is working to improve the information contained in the pregnancy section of product labeling and has been proactive in encouraging the collection of more and better data about drug effects during pregnancy (both to mother and fetus) through the use of pregnancy exposure registries. These prospective registries allow real world clinical practice data on risk (or lack of risk) to ultimately benefit patient care. The FDA provides a list of current pregnancy exposure registries atwww.fda.gov/womens/registries/default.htm.