Flu or prolonged fever during pregnancy increases autism risk

New research out of Denmark seems to show a higher risk of autism in babies born to women who had the flu while pregnant, and in those babies born to women who had a fever for longer than a week during pregnancy. In the study, women who had a normal pregnancy had an autism risk of about 1%.  The study, published in Pediatrics online November 12, 2012, was done as a combination of telephone interviews and gathering diagnoses of autism from the Danish Psychiatric Central Register. Women were not tested to see if they actually had the flu, but the study results do give some reason for caution. The study included over 96,000 children born in Denmark between 1997 and 2003. While most common infections during pregnancy did not seem to have any effect on the child, mom getting the flu during pregnancy seemed to double the risk of autism, and mom having a prolonged fever (about a week or longer) seemed to triple the risk of autism.

The good news is that even the highest risk group in the study, that with fever during pregnancy lasting a week or more, still only had an autism rate of 3%. The other piece of good news is that women are able to take actions to reduce their risk of becoming ill during pregnancy.

Many experts recommend that all pregnant women get a flu shot to help reduce the risk of getting influenza. Since flu shots are most effective against the strains of flu in the shot that year, and there are many different strains of flu, some women are concerned about how effective the shot really is. There are also some concerns about the safety of the shot, including the use of thimerosal (a mercury-based preservative) in some batches of flu vaccine. While the CDC states that the small amounts of thimerosal in flu vaccines have not been shown to cause harm, some people are still concerned because of how small the developing baby is. Studies have shown that Thimerosal accumulates in brain tissue and can contribute to neurological problems. Thimerosal has been removed from all vaccines given to children in the United States because of these concerns of possible mercury toxicity. Fortunately for those who want to get a flu shot, there are shots available without mercury.

There are also many other things a woman can do to support her immune system and reduce the likelihood of getting sick during pregnancy, or to get better more quickly if she does get sick. These are great to use in case the shot does not cover all of the common strains of flu out this year, or for those women who prefer to avoid the flu shot.

If you decide to get the flu shot during pregnancy:

  • Use the flu shot, not the nasal spray vaccine. Experts recommend against pregnant women using the flu vaccine nasal spray. The nasal spray contains live virus, and live virus vaccines tend to come with a higher risk of side effects and may result in the very infection they are trying to prevent, especially in people with less-active immune systems. The natural immune suppression that occurs during pregnancy makes live-virus vaccines a bad idea.
  • Ask for a single-dose unit to avoid mercury. Influenza vaccines are packaged as multi-dose units, or single dose units. Since the single-dose unit is used once, then thrown away, it is packaged without the preservative Thimerosal.
  • Support your immune system in other ways, too. A flu shot is not a cure-all. Flu shots can help prevent the flu, but there are still other illnesses that your body will need to fight off.

To support your immune system during pregnancy and reduce risk of illness:

  • Make sure you get enough rest. Go to bed early if you need to, or even set aside time for naps during the day.
  • Eat plenty of fresh foods to get the antioxidants, enzymes and other nutrients, like vitamin C and zinc, which help support your immune system.
  • Try an immune support supplement. If your doctor or midwife says it is ok, you can also take a nutritional immune support supplement containing vitamin C, zinc and other nutrients. Supplements with echinacea may be ok, but definitely avoid goldenseal.
  • Consider taking a glyconutrient supplement to support your immune system.
  • Exercise regularly to help your lymph system to clean out toxins in your body. Even walking and stretching can help move the lymph around and clear toxins.
  • Set aside time to relax. When your body is working harder because of stress, there is less energy and resources for fighting infection. Set aside time each day to pray or meditate. These “time-outs” help your body recover somewhat without being asleep, and help calm your mind so life’s bumps are easier to handle.
  • Minimize items in your environment and diet which make your body work harder. This includes toxins, allergens, sugars, processed foods, etc.
  • Drink plenty of water to flush out wastes.

Tips for reducing the chance of getting colds or the flu are excerpted from the Pocket Pregnancy Guide: Remedies so You Feel Great While Pregnant (due to be published as an e-book in late 2015).

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