When you're pregnant, you pay extra-close attention to nearly everything you put into your body, from a tuna fish sandwich to everyday pain medication. So you might also feel extra nervous about getting a flu shot or other vaccines. But some vaccines are actually crucial during pregnancy: "Being immunized not only protects the health of a pregnant woman, it protects her baby from the day it's born," says Sonja Rasmussen, MD, editor-in-chief of the Morbidity and Mortality Weekly Report for the Centers for Disease Control and Prevention (CDC).

Thanks to antibodies that are passed from mother to baby in utero, getting certain vaccines when you're pregnant can actually help defend your newborn from potentially deadly diseases. Keep yourself and your baby healthy by getting these two shots:

RELATED: Adult Vaccines: What You Need and When

Influenza (aka flu)

Flu vaccines are recommended for everyone 6 months and older, including pregnant women. Pregnant women get sicker from the flu and are especially vulnerable to complications from the flu, including hospitalization and death.

Getting the flu while pregnant can also lead to preterm birth, low birth weight, and other problems for the baby. Yet only about 50% of women get vaccinated during pregnancy, Dr. Rasmussen noted recently at a press event sponsored by the March of Dimes.

That stat is all the more alarming considering that a flu vaccine not only protects the mother, it also protects her baby from getting the flu up to 6 months (the age at which babies can be vaccinated themselves). And infants under 6 months are at especially high risk of complications from the flu, such as pneumonia.

The American College of Obstetricians and Gynecologists also urges all pregnant women to get a flu shot, during any stage of pregnancy. (Pregnant women should not get the nasal spray form of the flu vaccine, which contains a weakened live virus.)

RELATED: 10 Biggest Myths About the Flu

Tdap (tetanus, diphtheria, and pertussis)

Pertussis (the "p" in Tdap), otherwise known as whooping cough, is a highly contagious illness that causes violent, uncontrollable coughing. It can lead to serious complications, including pneumonia and trouble breathing, especially in infants and young children. (Listen to this super scary recording of a baby with whooping cough at Sounds of Pertussis.)

Recent years have seen a surge of whooping cough cases, peaking in 2012 with nearly 50,000 cases reported to the CDC. There were also 20 deaths, the majority of them babies younger than 3 months old.

Because of these dangers, experts now advise that pregnant women get a Tdap vaccine during every pregnancy. Research shows that Tdap is safe during pregnancy and helps protect babies until they are old enough to be vaccinated themselves (starting at 2 months). Yet only 14% of pregnant women get a pertussis vaccine, Dr. Rasmussen says.

Ideally, you should get Tdap during the third trimester—but no later than 36 weeks, to allow at least 2 weeks for your body to build up the maximum levels of protective antibodies, says Dr. Rasmussen. Your antibodies will decrease over time, so if you get pregnant again, you'll need another Tdap dose to protect that baby, too.

For even more protection, make sure your partner and anyone else who'll come into regular contact with your baby (grandparents, siblings, caregivers) has been vaccinated, too. The health of your baby is worth it.

RELATED: 7 Kinds of Cough and What They Might Mean