The Flu and Pregnancy

Why vaccination matters

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While some expectant mothers may believe that they should steer clear of the flu shot, the fact is that they are among the groups that are especially encouraged to get it.

The reasons for this recommendation, put forth by the CDC, relate to the changes in a pregnant woman’s body that make it easier for an infection to enter and harder to fight off.

The immune system undergoes changes when a woman is pregnant: recent studies have shown that it responds more aggressively to the flu virus. While this might appear to be a good thing, the abundance of immune cells in the lungs causes inflammation, making breathing more difficult.

A pregnant woman’s need for oxygen is greater than normal, and increased oxygen consumption is essential for the fetus to develop healthily. Inflammation of the lungs make it harder to get enough oxygen, and can lead to complications like pneumonia.

Lung capacity is already decreased during pregnancy as the belly becomes bigger, so this can add to the problem of proper oxygen consumption.

Pregnant women are also more likely to contract viruses, but not due to a weakened immune system, as one might expect. Instead, it is because of the pregnancy hormone progesterone. This hormone causes capillaries to become congested with blood, and causes the lining of nose and throat to swell, making pregnant women more susceptible to falling ill with the flu.

The flu shot is safe for pregnant women at any point during their pregnancy. Even after giving birth, it is important to get vaccinated, to avoid spreading the flu to the baby. One of the major advantages of getting the flu shot while still pregnant is that it provides immunity to the baby as well, and since infants cannot be vaccinated until they are at least 6 months old, it is the only safe method for immunizing a newborn. It is also recommended that anyone who cares for the baby gets vaccinated as well, including family members and babysitters.

Getting a fever from the flu early in pregnancy can increase the chances of having a baby with birth defects. Although the fever can be lowered with over-the-counter medicines, it is important to call a doctor when flulike symptoms are present during pregnancy. A doctor can prescribe medications that reduce the chances of complications from the flu, although the first line of defense against the flu for pregnant women is to get the flu shot.