Live oral vaccines

The data regarding the available oral vaccines, listed below, seem to indicate that these vaccines are safe and effective when used during pregnancy.

Our experience with the oral typhoid vaccine, however, is that there is a fairly high incidence of gastrointestinal side effects from the vaccine. As pregnancy is a state of altered GI function with nausea and reduced intestinal motility being part of the picture, we fear that side effects from this vaccine may be worse during pregnancy. For that reason we preferentially recommend the injectable vaccine during pregnancy.

Oral polio vaccine is no longer routinely used in the United States, but its use, if indicated, would appear to be safe.

The oral vaccines for cholera and traveler's diarrhea have not been extensively studied during pregnancy and so we have little data to present. Once again, however, we worry about gastrointestinal side effects. Furthermore, as cholera is rarely a risk to the traveler and because there are other available preventive measures for both cholera and diarrhea, we have not yet begun advocating the use of these vaccines.

Typhoid

1. Mazzone T, Celestini E, Fabi R, et al. Oral typhoid vaccine and pregnancy. Reprod Toxicol 1994 May-Jun;8(3):278-80. The ‘TELEFONOROSSO” a service provid­ing medical counselling to pregnant women on situa­tions that might pose a risk for their pregnancy received 21 inquiries from January 1990 to Decem­ber 1992 on the accidental administration of oral typhoid vaccine during the first trimester. Of these pregnancies, two ended in miscarriage in the 8th week, three were lost to follow-up, and 16 led to the birth of anatomically normal newborns. In one case, a newborn girl who was also exposed to tetanus toxoid and chloroquine prophylaxis had grade III vesicoureteral reflex and sepsis. Two additional newborns had jaundice treated with phototherapy and one had an obstetric palsy.
2. Hahn-Zoric M, Carlsson B, Mellander L, et al. The influence on the secretory IgA antibody levels in lactating women of oral typhoid and parenteral cholera vaccines given alone or in combination. Scandinavian Journal of Infectious Diseases, 1989;21(4):421-6

Polio

1. Centers for Disease Control. Poliomyelitis prevention in the United States. Morb Mortal Wkly Rep 49(RR-5):1-22, 2000.
2. Ornoy A, Ben Ishai P.: Congenital anomalies after oral poliovirus vaccination during pregnancy. Lancet 1993 May 1;341(8853):1162 Letter Despite being a live vaccine, the oral preparation (OPV) had previously been recommended when immediate protection was needed. (The recommendation for the nonimmune pregnant traveler is one dose of OPV prior to travel followed by completion of the regimen after delivery.)

3. Harjulehto-Mervaala T, Aro T, Hiilesmaa VK, et al. Oral polio vaccination during pregnancy: no increase in the occurrence of congenital malformations. Am J Epidemiol 1993;138:407–414. During a nationwide immunization campaign in Finland when several thousand pregnant women received the OPV, there was no increase in the occurrence of congenital malformations.
4. Harjulehto-Mervaala T, Aro T, Hiilesmaa VK, Hovi T, Saxen H, Saxen L. Oral polio vaccination during pregnancy: lack of impact on fetal development and perinatal outcome. Clin Infect Dis 1994 Mar;18(3):414-20

Cholera

1. Berger SA, Shapiro I. Re-emergence of cholera vaccine. J Travel Med 1997;4:58–60.
2. Clemens JD, Sack DA, Harris JR, et al. Field trial of oral vaccines in Bangledesh: results from three-year follow-up. Lancet 1990;335:270–273.
3. Sanchez JL, Trofa AF, Taylor DN, et al. Safety and immunogenicity of the oral, whole cell/recombinant B subunit cholera vaccine in North America. J Infect Dis 1993;167:1446–1449