Must weigh several factors : risk of exposure , maternal risk , fetal risk , risk from vaccine / toxoid .
Rule of thumb : No live vaccines unless :
1. Susceptibility / exposure probable and
2. Disease threat to woman / fetus - vaccine risk

Only routinely administrated immunization during pregnancy :
1. Tetanus - diphtheria toxoids
2. At-risk group for Hep B virus

MMR : 3 months before pregnancy or immediate postpartum
Polio / yellow fever vaccine - when traveling to endemic area

Immune globulins :
1. After exposure to : measles , Hep A , B , tetanus , chickenpox or rabies
2. VZIG for newborns of mothers who develop chickenpox 5 days before , until 2 days after delivery
3. All women without a history of chickenpox should be passively immunized with VZIG within 98h of an exposure to chickenpox