Several mainstream news sources, to include USA Today, have recently posted articles on miscarriage and the influenza vaccination. Newly pregnant mothers want to know, is the flu vaccine safe in pregnancy? The flu vaccine is recommended for all pregnant women and women are told there is little to no risk in receiving the vaccination during their pregnancy. Yet many vaccinations haven’t been tested in pregnant women. 
So let’s talk about it. This is the recently published study by the CDC that shows an increased risk of miscarriage after receiving the influenza vaccination containing pH1N1. The 2017-2018 influenza vaccination looks to have this virus in it. Here are the three viruses for this season:
- an A/Michigan/45/2015 (H1N1)pdm09-like virus (updated)
- an A/Hong Kong/4801/2014 (H3N2)-like virus
- a B/Brisbane/60/2008-like (B/Victoria lineage) virus
The risk of miscarriage was only looked at for the 1 – 28 days following the vaccine and the woman had to have received a prior influenza vaccine which contained pH1N1 as well. The 2016-2017 influenza vaccine contained A/California/7/2009 (H1N1)pdm09-like virus (I am only listing H1N1). While the study authors stated that it cannot establish a causal relationship, the association of receiving the flu vaccine during pregnancy and having a miscarriage (SAB) was significant.
What we do know is that pregnant women ARE at a higher risk of contracting illnesses during pregnancy and the flu is one of those illnesses. I used to receive the flu vaccine but as I have aged, I have become allergic to the ingredients in many vaccines. Even if I weren’t allergic, I personally would not receive the flu vaccination, or any vaccination for that matter, during pregnancy. I was pregnant this year and in February, I contracted Influenza B. Not a single person in my family was sick or became sick. I was miserable and I did what I could to protect my baby.
I am not certain where I contracted Influenza B but I do work in a hospital so maybe that’s where I picked it up. My symptoms did not present normally. I did not have a fever at all but I felt very sick, headache, muscle aches, heart palpitations, and I felt like I was struggling to breathe. I put off visiting the ER, mostly because my husband did not want to take me in the middle of the night. In addition, we knew the visit would be costly and that is always a consideration.
It was not easy waiting through the night not to be seen. I couldn’t sleep and honestly, I wanted to be put out of my misery. Instead of going to the ER, I asked for a walk-in appointment the following morning. When I arrived at the clinic, the doctor was upset I was there and not in the ER. While my oxygenation was fine, I was clearly struggling to breathe. Their concern was that I had been breathing rapidly (over 33 respiration’s per minute) for more than 12 hours and my body would give out and I would “crash.” That was their nice way of saying, die.
I felt absolutely awful but I wanted to avoid the ER so I asked for any testing or procedures they could do in the office. They said they couldn’t test for the flu in their clinic and I would have to go to the ER for that, but they would give me a nebulizer treatment and see if that helped. I did not want to take any medication during my pregnancy but I needed some relief. I was convinced to take the treatment in hopes that it would help and I would avoid the ER.
It did nothing, so we were sent to the ER. I again received an ineffective breathing treatment and was sent home. I was told my blood labs were normal and that my influenza test hadn’t come back but they would call if it was positive. They had no explanation for my illness, other than I must have a bad cold (even though I wasn’t congested at all) and because I was “old” and pregnant, I was responding harshly to the virus. I later learned that my labs were not “normal” but the doctors didn’t believe my labs were indicative of anything.
During the 15 minute drive home, the doctor called my husband to confirm that I had Influenza B. I was surprised they didn’t admit me as my respirations were still horrible but they sent me home with Tamiflu. I hesitated to take the medication. There are no studies of the use of this drug in pregnant women but I needed relief. In addition, I had been symptomatic beyond the 48 hour window for the effectiveness of this drug.
I conducted a little research before consuming the drug. I had immense anxiety over this. I was well into my second trimester and was passed the gestation where the defects could occur. There were three babies whose mothers had taken the drug who had defects (although some babies were aborted but according to the study, this was not statistically significant). 24 hours after taking Tamiflu, I began to feel relief. By 72 hours after Tamiflu, I was feeling well although exhausted.
I worried throughout my pregnancy that I somehow hurt my baby from the Tamiflu. Only time would tell and a future ultrasound did not show any defects with her heart. Once she was born “normal” I felt okay about taking Tamiflu although it’s still possible she could have been affected but we won’t know until later in her life. So far, all is well with her.
Despite the CDC study, women are still urged to get the flu shot in pregnancy. Why? The reasons cited are to reduce hospitalizations due to complications from the flu, morbidity and mortality, and to pass on antibodies to the unborn baby. This study shows that the influenza vaccine in pregnancy is 91.5% effective in preventing hospitalization of the infant in the first six months of their life (this does not say the infant does not contract influenza). I am sure my daughter has antibodies for Influenza B since I had it.
So what should a pregnant woman do? There is clearly a relationship between miscarriage and having received the influenza vaccination so it would be up to the woman to assume the risk. Do the research, make the decision. I don’t ever recommend just listening to a doctor. I want to be very clear in what I am saying; the doctors recommendation IS important; however, it should not be the only deciding factor. If a woman receives the vaccination and then miscarries, how would she feel knowing that ?
I know I would never forgive myself so I choose not to receive vaccinations during pregnancy and most especially during the first trimester. Only you can decide if it’s right for you. As someone who has experienced miscarriage twice, I worry so much during subsequent pregnancies about losing the baby and anything I can do to reduce that anxiety is helpful. Once the baby is born, I know there are many things I can do to help keep the baby healthy and I follow all those precautions and recommendations during such a fragile time.
Making the decision to receive or not receive the flu vaccine is difficult. There seems to be good research out there to help make an informed decision, although much of it is irrelevant if the baby does not make it to term if the flu vaccine causes miscarriage.
