Levels of total PT-IgG, and PT-IgG total relative avidity index, total absolute avidity, and fractional absolute avidity levels of very low to very high avidities in pregnant women at the time of delivery, and infants at the time of birth and at 2 months of age after vaccination during pregnancy with different formulations of recombinant pertussis vaccines or chemically detoxified pertussis vaccine. This evidence concerns the gene F2 and pertussis.