There are two main reasons all pregnant women should receive these vaccines in pregnancy: first, for the benefit of their own health, and second to protect their baby in-utero as well as for the first several months of life.
The Flu Shot
Pregnant women are particularly susceptible to an illness such as influenza. The immune system undergoes normal changes during pregnancy, which can increase the risk of complications from the flu. Pregnant women who acquire the flu are also at higher risk of pregnancy related complications, such as preterm labor, pneumonia, and serious illness requiring hospital admission.
When you receive a vaccine, it activates your body to construct antibodies, which are proteins that our immune system produces in response to invading pathogens such as bacteria or viruses. It takes about two weeks after an immunization for the body to build up these protecting antibodies. The antibodies travel all through the bloodstream, seeking out the pathogen they were designed to identify, and helping the body to recognize, attack and ultimately clear out the invading pathogen.
Unlike adults, newborn babies cannot immediately receive vaccinations to the flu or whooping cough, and therefore need assistance in generating their own protective antibodies. However, if the mother receives a vaccine during pregnancy, the antibodies she generates will passively transfer from her to the baby, allowing the baby to be born with a blood stream full of this precious gift from mom. Without this protection, the baby is vulnerable to illnesses such as the flu or whooping cough, until they can receive their own flu vaccinations at 6 months.
Pregnant women should receive the flu vaccine early in the flu season, as soon as the vaccine is available. All flu shots available are recommended for use in pregnant women with the exception of the live intranasal vaccine (which is no longer on the market this year). The flu shot can be given at any point in time during pregnancy.
All pregnant women should also receive a Tdap vaccine between 27 and 36 weeks of pregnancy. This single shot protects against tetanus, diphtheria, and pertussis, commonly known as whooping cough. Whooping cough is a serious disease that can be deadly for babies, who are not able to receive their own vaccination until they are two months old. To help protect baby during the first two months of life, all pregnant women should be vaccinated, passing on protective antibodies to baby from day one. The antibodies dwindle with time, so it is important for every pregnant woman to get the vaccination with every pregnancy. It is also important for all caretakers to update their pertussis vaccination as well, which helps to surround the infant in a protective cocoon.
It is also valuable to make sure your vaccinations are up to date before you get pregnant. Not every vaccine is safe during pregnancy. If you are planning to travel outside the United States or are at high risk for infection, talk to your doctor or midwife about recommendations for other vaccinations during pregnancy. These may include anthrax, Japanese encephalitis, polio, rabies, smallpox, yellow fever, hepatitis A and B.