Vaccinations in Pregnancy - American Family Physician

Tetanus and Diphtheria The tetanus and diphtheria toxoids vaccine (Td) is effective in preventing tetanus and diphtheria, two potentially life-threatening conditions. Diphtheria is an infection of the nasal, pharyngeal, laryngeal, or other mucous membranes that can cause neuritis, myocarditis, thrombocytopenia, and ascending paralysis. Tetanus infection can cause production of a neurotoxin, leading to tetanic muscle contractions. Td toxoid is routinely recommended for susceptible pregnant women. While no evidence exists to prove that tetanus and diphtheria toxoids are teratogenic, waiting until the second trimester of pregnancy to administer Td is a reasonable precaution, minimizing any concern about the theoretic possibility of such reactions. Previously vaccinated pregnant women who have not received a Td vaccination within the past 10 years should receive a booster dose. Pregnant women who T he administration of vaccines during pregnancy poses a number of concerns to physicians and patients about the risk of transmitting a virus to a developing fetus. This risk is primarily theoretic. Livevirus vaccines are therefore generally contraindicated in pregnant women. According to the Centers for Disease Control and Prevention (CDC), if a live-virus vaccine is inadvertently given to a pregnant woman, or if a woman becomes pregnant within four weeks after vaccination, she should be counseled about potential effects on the fetus. Inadvertent administration of these vaccines, however, is not considered an indication for termination of the pregnancy. No evidence shows an increased risk from vaccinating pregnant women with inactivated virus or bacterial vaccines or toxoids. Therefore, if a patient is at high risk of being exposed to a particular disease, if infection would pose a risk to the mother or fetus, and if the vaccine is unlikely to cause harm, the benefits of vaccinating a pregnant woman usually outweigh the potential risks. Physicians should consider vaccinating pregnant women on the basis of the risks of vaccination versus the benefits of protection in each particular situation, regardless of whether live or inactivated vaccines are used. Adult immunization rates have fallen short of national goals partly because of misconceptions about the safety and benefits of current vaccines. The danger of these misconceptions is magnified during pregnancy, when concerned physicians are hesitant to administer vaccines and patients are reluctant to accept them. Routine vaccines that generally are safe to administer during pregnancy include diphtheria, tetanus, influenza, and hepatitis B. Other vaccines, such as meningococcal and rabies, may be considered. Vaccines that are contraindicated, because of the theoretic risk of fetal transmission, include measles, mumps, and rubella; varicella; and bacille CalmetteGuérin. A number of other vaccines have not yet been adequately studied; therefore, theoretic risks of vaccination must be weighed against the risks of the disease to mother and fetus. Inadvertent administration of any of these vaccinations, however, is not considered an indication for termination of the pregnancy. (Am Fam Physician 2003;68:E299-309. Copyright© 2003 American Academy of Family Physicians.) Vaccinations in Pregnancy