CPT code 90715: Tdap Vaccine (Tetanus, Diphtheria, and Pertussis)

The physician or other qualified health care professional generally administers the Tdap vaccine once in adulthood, but boosters are recommended every 10 years thereafter unless otherwise indicated.

Yes, the Centers for Disease Control recommends it between 27–36 weeks gestation.

Often, yes, when given as part of routine immunization.