This Physician’s Assessment of Flu Vaccines in Pregnancy

By Cindy Schneider, M.D., SafeMinds Scientific & Clinical Advisory Board Member

Flu vaccines and pregnancy

Primum non nocore, the philosophy attributed to Hippocrates, is taught to every medical student in the country. A doctor has two objectives at all times: The obvious objective is to heal, but the overruling objective, before all others, is to do no harm.

All interventions carry some risk, and we often accept these risks. A patient with cancer may willingly undergo chemotherapy with full knowledge that there will be serious, even potentially life-threatening side effects.

When the risk of doing nothing is quite high, the risk of any given intervention may be justifiable. But the burden of proof of safety should be far greater for interventions designed to prevent illness, rather than treat it.

Vaccinations are such an example.

Vaccines are given to healthy individuals in the hope that they will provide protection against infection.

But hope is not science. We will explore the science.

In the case of flu shots given in pregnancy, there are two individuals to consider. If recommended, an influenza vaccine must be safe for both a mother and her unborn child. Many physicians and researchers question this purported safety.

In the later stages of pregnancy, the growing baby occupies space normally available for a mother’s diaphragm to expand. This can lead to shortness of breath, even under normal conditions. Because of this physiological change, pregnant women who contract influenza are at greater risk of breathing difficulties and hospitalization than women who contract influenza but are not pregnant. Given this observation, the Centers for Disease Control and Prevention (CDC) recommended the administration of influenza vaccines to pregnant women in 2004.  Because a mother’s antibodies freely cross the placenta, it was thought that some degree of protection might be provided to her baby as well. The safety and efficacy of flu vaccination in pregnancy are in question, however.

In a study published in the May issue of the British Medical Journal, Giuseppe Traversa and colleagues assessed maternal, fetal, and neonatal outcomes of women given the influenza A/H1N1 vaccine. The outcomes of over 86,000 pregnancies revealed that vaccinated women had significantly higher rates of gestational diabetes and eclampsia. Eclampsia is the development of seizures in a woman with severe toxemia (also known as pre-eclampsia), a condition characterized by high blood pressure and protein loss in the urine. Eclampsia is fatal in 2% of women and can result in long-term health problems in those who survive. Fetal complications, including neurological damage and death, are common. Both gestational diabetes and eclampsia are related to inflammation and immune dysregulation, making the connection to the immune stimulation of the flu vaccine very plausible.

Do flu vaccines cause inflammation in pregnant women?

There has been surprisingly little research in this area, but a study by Christian et al  following pregnant women given a seasonal flu vaccine found an increase in two inflammatory markers, C reactive protein (CRP) and tumor necrosis factor-alpha (TNF-a). Increases in these inflammatory compounds indicate a significant level of inflammation, which was identified during the first two days following vaccination.

This increase of inflammation was confirmed in a study published this week that documented a higher level of post-vaccine immune activation in pregnant women than in non-pregnant controls receiving flu vaccines.

An earlier study by Lisa Christian, Ph.D. and her colleagues found that pregnant women suffering from depression developed a more marked inflammatory response to influenza vaccines than women who did not have symptoms of depression.

There is reason to be concerned about these findings. A recent study by Alan Brown, M.D. and his colleagues of over 1.2 million pregnant women found that elevations in CRP, the same marker of inflammation that increases after flu vaccination, are associated with a 43% greater risk of having a child with autism.

Millions of women who are pregnant or hoping to become pregnant in the near future now face the annual decision of whether or not to receive a flu shot.  This is not a decision that should be made without careful consideration of the new data available.

While intended to protect pregnant women and their babies, influenza vaccines may inadvertently be doing more harm than good.

In addition to the unwanted inflammatory and immune-stimulating effects of flu vaccines, there are many concerns about their formulation. Mercury, a potent neurotoxin, is found in the preservative thimerosal, which is 49.6% ethylmercury by weight. Because the FDA recommended the immediate reduction or elimination of mercury in infant vaccines in 1999 and the 2001 Institute of Medicine report on thimerosal recommended “full consideration be given by appropriate professional societies and government agencies to removing thimerosal from vaccines administered to infants, children, and pregnant women in the Unites States,” many people, including physicians, are under the impression that all vaccines are now mercury free. As most of our readers know, that is NOT the case.

Mercury is a fat-soluble toxin that easily crosses the placenta and accumulates in fetal tissue. For reasons that are not yet clear, fetal mercury levels become even higher than maternal levels. The effects of mercury on brain development can be devastating.

In spite of these known facts, thimerosal-containing flu vaccines are routinely given to pregnant women. The mercury content of these flu shots is 250 times higher than the level the EPA classifies as hazardous waste. Unused mercury-containing flu vaccines must be disposed of as hazardous waste, yet they are approved for use in pregnant women and infants.

We are currently being bombarded by reminders to get our annual flu shot. Pharmacies, grocery stores, and news reports would lead us to believe that everyone needs one. Obstetricians are routinely recommending them to their patients, as advised by the CDC and their medical organizations, but they are likely unaware of the research findings reviewed above. It is also unlikely that your doctor knows that the largest trial of influenza efficacy in pregnancy to date, following nearly 50,000 pregnant women over five flu seasons, found that the rate of influenza-like illness in vaccinated women was identical to the rate of illness in women who were not vaccinated.

I completed my obstetrics and gynecology residency in 1990.  At the time, we were taught that vaccines should never be given during pregnancy, as it is a delicate state of immunosuppression.  A woman’s immune system must remain partially suppressed to prevent the rejection of her baby, who carries proteins coded by paternal genes. Any immune stimulation could tip the scales, allowing a mother’s immune system to recognize fetal tissue as foreign and mount an immune response against it. This phenomenon has been documented by Braunschweig, Zimmerman, Pirasa, and other researchers in a percentage of mothers whose children developed autism.

Many women question the wisdom of flu vaccination during pregnancy, but are unable to articulate their concerns during prenatal visits. I am a former obstetrician who has spent over 24 years protecting women and children from environmental toxins and the past 19 years studying the potential causes of the autism epidemic. Allow me to be the bridge between you and your doctor, family members, or friends who question your decision not to get vaccinated while pregnant.

I have included a list of references cited for your doctors or other health care providers to review and I encourage you to print this article and bring it to your doctor’s office. Please help us educate both physicians and the general public by sharing this information by email, Facebook, and printed copies.

As a physician, researcher, and mother of two adults with autism, I have studied this subject extensively. In the face of so much evidence of risk and an unconvincing promise of benefit, I cannot recommend vaccinations of any kind during pregnancy.

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