1. American College of Obstetricians and Gynecologists’ immunization web site. Available at http://www.immunizationforwomen.org.
2. Centers for Disease Control and Prevention's Immunizations for Pregnant Women. Available at http://www.cdc.gov/vaccines/parents/pregnant.html.
3. Diphtheria, tetanus, and pertussis, recommendations for vaccine use and other preventive measures;MMWR,1991
4. Updated recommendations for use of tetanus toxoid, reduced diphtheria toxoid and acellular pertussis (Tdap) vaccine from the Advisory Committee on Immunization Practices, 2010;MMWR,2011
5. Tetanus vaccine position paper;WHO;Wkly Epidemiol Rec,2006