Pregnant and feeling under the weather? Figuring out if you have a cold or flu is essential, as influenza can blossom into some serious and deadly conditions for a pregnant woman.

With all the other changes your body is now undergoing, the last thing you need is a bout of the flu. Physiological changes due to pregnancy include the immune system and heart and lungs. Influenza infection, with its associated symptoms, can cause a host of pregnancy problems including premature births. So the recommendation to get a flu shot right away, which is completely safe for pregnant women, is a solid suggestion.

This will boost a woman’s immune response to the flu virus and will hopefully stave off the nasty bug. Here are a few important facts to keep in mind.

1. Changes to a pregnant woman’s immune system make her vulnerable to infections and other illnesses. The immune system is normally depressed during pregnancy so that the mother’s body doesn’t reject the growing baby as a foreign body. But a lowered immune response means a woman is at a higher risk for illnesses such as pneumonia, a life-threatening infection.

A recent study by Stanford University has put forth a different theory as to the increased risk of serious illnesses in pregnant women. In the lab, white blood cells, which fight infections in the body, were infected with the influenza virus. These infected cells attracted more white blood cells. These excessive cells irritate the lungs, causing more cells to attack. This mechanism may be responsible for excess fluids in the lungs, leading to pneumonia.

Dr. Catherine Blish, assistant professor of infectious diseases at Stanford School of Medicine and the study’s senior author said, “Having too many immune cells in the lung can cause inflammation that makes it hard to breathe,” she says. “If these findings are confirmed in bigger studies and then natural infection, they could explain why pregnant women do so poorly.” There is something in the influenza virus that brings out this response in immune cells, said Blish.

2. Pneumonia is a serious illness that is a complication of the flu. Pregnant women, as we have seen, are more at risk for developing severe illnesses without an annual flu shot. It is a respiratory infection that causes inflammation of the lungs, causing breathing difficulty.

If you experience flu-like symptoms, call your doctor right away. There are antiviral drugs that will lessen the severity and duration of the flu. It should be given within 48 hours of symptoms for the greatest effectiveness but it may be administered later as well.

Influenza infections can cause preterm labor and premature birth, stillbirths, small size for the age of the newborn and perinatal death, or early newborn death.

In the first month of pregnancy, a fever can be disastrous to a fetus. Fevers in the mother could cause neural tube disorders such as spina bifida and anencephaly. In spina bifida, the fetal spinal column doesn’t close completely and there is typically nerve damage affecting the legs. Anencephaly is where most of the brain and skull doesn’t develop. The infant is usually stillborn or dies shortly after death.

In the second and third trimesters, a mother’s lungs need more oxygen since she is breathing for herself and the baby. But the growing belly puts pressure on the lungs, making them work harder for the same amount of oxygen in a smaller space. A mom’s heart is also working harder to supply blood to the baby as well as herself. This creates physiological stress on the mother’s body, and her immune system.

3. Maternal influenza cancer risks. Though these are rare cancers we are discussing, they are still of serious concern during pregnancy. It was found that cancers such as neoplasms of lymphatic glands and of the tissues that develop all blood cells had a four-time increase of occurrences. There is also a risk of neuroblastomas. This is cancer that develops from immature nerve cells, and most commonly found around adrenal glands, which have the same origins as nerve cells. These glands sit atop the kidneys.
   

4. Psychological effects of the mother’s flu on children. There was a study published in the JAMA Psychiatry which found a strong correlation between pregnant women who had the flu at any time in her pregnancy and bipolar disease (BD) in the birthed child later in her life.

“Offspring exposed to maternal influenza infection at any time during pregnancy were nearly four times more likely to develop BD than those who were not exposed,” the researchers concluded. One possible explanation is that it has something to do with the woman’s immune response.

Previous studies, some inconclusive, linked pregnant women with influenza to psychological illnesses such as schizophrenia, BD and psychosis in children born to the women. Studies of both schizophrenia and BD are beginning to shed light on the mechanism that may cause these two illnesses. There have been similarities discovered between the illnesses that may influence the further studies of psychological disorders.

So flu shots anyone? The best way to prevent the flu and lessen its severity in pregnant women is to get a flu vaccination as early in the season as possible. The shot also has benefits for your newborn. Breastfeeding passes antibodies that the mother’s body has developed onto the nursing baby. This helps babies fight infections, especially in the first six months of their lives as they cannot yet get immunized. Studies have found that breastfed babies of inoculated moms get sick less often and the illness is less severe. Protection for the infant was found to last about four months

And for those of you who heard certain rumors about flu vaccines, they are not true. There is no connection between getting the flu shot and miscarriages. Also, there is a tiny bit of thimerosal, or a form of mercury, in the vaccine. It acts as a preservative. Studies have shown that there is no link between thimerosal to autism or attention deficit hyperactivity disorders.

So no excuses. The most prudent thing a pregnant woman can do is to get a flu shot in a timely manner. It may be the best decision for both you and your baby’s health.