All pregnant women at 28 - 32 weeks should receive a dose of Tdap vaccine against pertussis in order to ensure the transfer of specific antibodies to their babies.
Usually, the newborn babies receive the Tdap as part of the 6-in-one vaccine (Infanrix Hexa) at 2, 4 and 6 months of age. The single Tdap vaccination for pregnant women aims therefore to offer protection for newborn babies from birth and till they will reach 2 months.
Pregnant women could receive this vaccine before or after the 28 - 32 weeks interval, but it may not be that active.
In the case of babies born before 32 weeks, it is recommended that the family contacts to receive the Tdap vaccine to protect the newborn.