What vaccine should be administered to a Prima Gravida (first-time pregnant woman) at her first Antenatal (prenatal) visit?

Vaccination at First Antenatal Visit for Prima Gravida

At the first antenatal visit, assess the patient's tetanus-diphtheria vaccination status and administer Td (tetanus-diphtheria toxoid) if she has not completed a primary series or if ≥10 years have elapsed since her last dose; however, do NOT administer Tdap at this visit—reserve Tdap for 27-36 weeks gestation during this pregnancy. 1, 2

Tetanus-Diphtheria Assessment and Primary Series

For unvaccinated or incompletely vaccinated women:

• Women who have never received tetanus-diphtheria vaccination should begin a primary series consisting of three doses of Td during pregnancy 3
• The first two doses should be administered at least 4 weeks apart 3
• The third dose should be given 6-12 months after the second dose 3
• Women who previously received only one or two doses should complete their primary series during pregnancy 3

For previously vaccinated women:

• If a pregnant woman has completed a primary series but ≥10 years have elapsed since her last dose, administer a Td booster at the first visit 3
• This early Td dose does NOT replace the Tdap dose required at 27-36 weeks gestation 1, 2

Critical Timing: Why NOT Tdap at First Visit

Tdap should be reserved for 27-36 weeks gestation, NOT administered at the first antenatal visit, for the following reasons:

• Administering Tdap between 27-36 weeks maximizes transplacental antibody transfer to provide passive immunity to the newborn during the most vulnerable first months of life 1, 2
• Maternal antibodies wane quickly—women immunized during the first or second trimester have shown low antibody levels at term 2
• Active transport of maternal immunoglobulin G does not substantially occur before 30 weeks of gestation 2
• Maternal Tdap vaccination during the 27-36 week window is 80-91% effective in preventing infant pertussis 2

Additional Vaccines to Consider at First Visit

Influenza vaccine (if during flu season):

• Inactivated influenza vaccine should be administered at any time during pregnancy, including the first visit, if the patient will be pregnant during flu season (October to May) 1, 4, 5
• Only use inactivated influenza vaccine (IIV) or recombinant influenza vaccine (RIV)—never live attenuated influenza vaccine (LAIV) 1
• Pregnant women face disproportionately higher risks from influenza infection, including increased rates of severe illness and adverse pregnancy outcomes 1, 6

Hepatitis B vaccine (if indicated):

• Prenatal screening of all pregnant women for HBsAg is recommended 3
• If the patient is at risk and not previously vaccinated, hepatitis B vaccine can be safely administered during pregnancy, as it contains only noninfectious HBsAg particles 3
• Pregnancy or lactation should not be considered a contraindication to hepatitis B vaccine for persons who are otherwise eligible 3

Vaccines to AVOID During Pregnancy

Live-virus vaccines are contraindicated:

• Live-virus vaccines (MMR, varicella, LAIV) should not be given to pregnant women due to theoretical risk to the developing fetus 3, 7
• These vaccines should be administered postpartum, preferably before hospital discharge 3

HPV vaccine is contraindicated:

• HPV vaccination is explicitly contraindicated during pregnancy and should be deferred until after pregnancy completion 1

Common Pitfalls to Avoid

• Do not administer Tdap at the first visit thinking you are "getting ahead"—this will result in suboptimal antibody levels at delivery and reduced protection for the newborn 2
• Do not skip the Td booster at the first visit if indicated—this provides maternal protection against tetanus and diphtheria throughout pregnancy 3
• Do not forget to document vaccination history thoroughly—this determines whether a primary series or booster is needed 3
• Do not delay influenza vaccination if the patient presents during flu season—maternal influenza infection carries significant risks 1, 4, 6