The immunity you get from the vaccine will pass to your baby through the placenta. The placenta is on the inside of your womb and links your blood supply with your unborn baby. This immunity will help protect your baby in the first few weeks of life when they are most vulnerable, up until they are old enough to have their first whooping cough vaccine at eight weeks.
The vaccine also protects you from getting whooping cough and lowers the risk of you passing it on to your baby.