By now, you’ve probably seen the news articles, like this one, reporting on the Danish study published in Pediatrics that found “that maternal influenza infection was associated with a twofold increased risk of infantile autism” and that “prolonged episodes of fever caused a threefold increased risk of infantile autism.” You’ve probably already been told that this is even more reason for pregnant women to get their flu shots.
While I am not a doctor, I do want to make sure that, if you are pregnant, you are armed with all of the facts to make an informed decision. Somewhere along the way, informed consent kind of fell to the wayside. We, as patients, are regularly not given all the information needed to give “informed consent.”
As you consider whether or not to get the advised flu shot if you are pregnant, please take some time to consider other points.
Avoiding the Flu in General
Let’s just say that getting the flu and other illnesses is the cause of autism, and ignore the fact that the flu has been around as long as we can remember and autism at the rate we are seeing is a new concern for humankind…
In the Huffington Post article, Catherine Pearson wrote, “The Centers for Disease Control and Prevention recommends a flu shot for everyone who is at least six months old, and includes pregnant women on its list of people for whom vaccination is particularly important.” And that’s totally true; the CDC does say that. But there’s also plenty of evidence to suggest that getting enough vitamin D would be a good idea to avoid getting the flu, but neither the CDC or the media reports about this Danish study are making that suggestion, even though patients are supposed to be making informed consent when getting vaccinations, not just consent.
FOOD FOR THOUGHT: Compare how often have you been offered a blood test to check for vitamin D deficiency to how often you’ve been offered a flu shot?
I explain the relationship between the flu and vitamin D connection in a previous post if you don’t know why I bring this point up.
It’s also important to remember that getting the flu vaccine isn’t necessarily going to protect a woman from getting the flu. No for real. There’s many variables including your own health, the particular strains of flu going around, and much more. The vaccines own inserts mention that it might not actually work on you anyway.
READ ALSO: Why vitamin D levels should be considered during pregnancy in general & for fetal development.
The Flu Vaccine During Pregnancy
The CDC, most US doctors and the media proclaim the flu vaccine to be safe to use during pregnancy. The CDC says that the nasal spray version of the flu shot is not to be given to pregnant women. That means pregnant women are supposed to get either the intradermal vaccine or one of the intramuscular vaccines. Let’s look more carefully at the vaccines that are available in the US during the 2012-2013 flu season according to the CDC.
Fluzone Intradermal- Consider what the manufacture’s own prescribing information says about this flu vaccine’s use during pregnancy:
“A developmental and reproductive toxicity study has been performed in female rabbits at a dose approximately 20 times the human dose (on a mg/kg basis) and has revealed no evidence of impaired female fertility or harm to the fetus due to Fluzone Intradermal. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, Fluzone Intradermal should be used during pregnancy only if clearly needed. Healthcare providers are encouraged to register women who receive Fluzone Intradermal during pregnancy in Sanofi Pasteur Inc.’s vaccination pregnancy registry by calling 1-800-822-2463.” NOTE: According to the CDC, the intradermal flu vaccine is not ok for anyone under 18 or over 64 either. So, pregnant teenagers would automatically not qualify for this version of the flu shot.
Fluzone Intramuscular- Consider what the manufacturer’s official FDA information says about this flu vaccine’s use during pregnancy:
“Pregnancy Category C: Animal reproduction studies have not been conducted with Fluzone. It is also not known whether Fluzone can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Fluzone should be given to a pregnant woman only if clearly needed.”
Fluvirin Intramuscular- Again, the manufacturer’s official FDA information states:
“Pregnancy Category C: Animal reproduction studies have not been conducted with Fluvirin®. It is also not known whether Fluvirin® can cause fetal harm when administered to a pregnant woman or can affect reproduction capacity. Fluvirin® should be given to a pregnant woman only if clearly needed.”
Fluarix Intramuscular- Consider that the prescribing information from the manufacturer states:
“A reproductive and developmental toxicity study has been performed in female rats at a dose approximately 56 times the human dose (on a mg/kg basis) and revealed no evidence of impaired female fertility or harm to the fetus due to Fluarix. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, Fluarix should be given to a pregnant woman only if clearly needed.”
Flulaval Intramuscular- Consider that the manufacturer’s official FDA information also states:
“A reproductive and developmental toxicity study has been performed in female rats at a dose approximately 56 times the human dose (on a mg/kg basis) and revealed no evidence of impaired female fertility or harm to the fetus due to Flulaval. There are, however, no adequate and well-controlled studies in pregnant women. Because animal reproduction studies are not always predictive of human response, Flulaval should be given to a pregnant woman only if clearly needed.” Note: This vaccine is only indicated for people over the age of 18 as well, so pregnant teens would not be able to get this flu shot.
Afluria Intramuscular- Consider the package insert from the manufacturer states:
“Safety and effectiveness of AFLURIA have not been established in pregnant women or nursing mothers and in the pediatric population below 6 months of age.”
These are your options for the flu shot if you are pregnant. Needless to say, these facts aren’t mentioned regularly in mainstream media, but I feel that these facts are pertinent to making informed consent prior to receiving the flu vaccine during pregnancy.
Correlation Does Not Mean Causation
This autism study was a population-based cohort study consisting of 96, 736 children aged 8 to 14 years and born from 1997 to 2003 in Denmark. Cohort studies do aid in observing possible causal associations, but determining true causality usually requires further experimental trials. The children who developed autism in this study accounted for only 1% of the children in the study. There are many factors that would need to be looked at at this point. For example, perhaps the flu didn’t cause the autism, perhaps the flu and autism have a shared nutritional deficiency that increases the risks of both. Perhaps they have a shared exposure to certain toxins or certain foods.
There are many variables here and the study itself explains this. Contrary to media reports, the researchers did point out that because many adjustments were made during the study and because the study relied on the mother’s answers and not their medical record, a definitive link between the flu or fevers and autism really couldn’t even be made. I am not discounting the information in this study. It’s a great tool for observation. I just want to make sure that if you are pregnant, you see the complete picture.
Doctors are already using this study to promote getting the flu shot during pregnancy For example, Dr. Colleen Boyle, director of the National Center on Birth Defects and Developmental Disabilities who was not involved with this study commented in regards to it, ”This is flu vaccine season so pregnant women should get the flu vaccine immediately.”
If you’re pregnant, you have a right to be made fully aware before giving “informed consent” during the most crucial developmental period of your child’s life.
Disclaimer: This article is not intended to be used as medical advice. This is not a substitute for professional medical advice or care. It is intended to be used as a tool for open discussion with your medical professional.



