Just as flu season begins, the news channels and press have been peppered with items citing that a new link between the flu vaccine and the rate of miscarriage has been uncovered. According to the news, a study had come forth within the scientific community that found a connection between women who had received the annual flu vaccine and an increased likelihood of miscarriage. The news, regardless of what medium it was presented in, was scary. Further, the timing of this news could not have been worse: flu season 2017-18 is just starting. However, the researcher in me wanted to take a deeper dive into this new information and withhold an opinion until I reviewed the data.
After a thorough review, this latest study does not change my opinion, nor that of my fellow expert colleagues in professional organizations: Flu shots are necessary, and safe, for pregnant women to prevent the incidence of flu and the horrible consequences that come with it.
Flu shots are necessary, and safe, for pregnant women to prevent the incidence of flu and the horrible consequences that come with it.
What the News Doesn’t Tell You
The study in question was undertaken by noted researchers in the field of influenza. However, I had several issues with their study. First, the researchers did not set out to explore a link, or relationship, between the flu vaccine and miscarriage; what they proposed, then, was a secondary finding. In this small-scale study, there are a lot of words like “may”, “possibly” or “could” and no definitive language saying that there is a link between miscarriage and the flu vaccine. Further, the women in this study were broken down into subgroups: women who miscarried and women who had not, then broken down into further subgroups by age. Risk, then, was hard to ascertain. The risk for miscarriage, then, existed in each category. In research, we calculate our data to establish a confidence interval, or a mathematical degree of “certainty” so we can say, with confidence, the findings of a study are significant, applicable and highly representative of how the rest of the population would respond. This study, however, had a wide confidence interval, meaning there was plenty of “wiggle” room in the data for it to be both right in some instances and wrong or not applicable in others. Lastly, the researchers propose possible mechanisms that could explain how the flu vaccine could increase the risk of miscarriage, but there’s no evidence to support their suggestions. A biological basis for their observations, then, had not been established.
The data from the study is interesting, but not compelling, at this point, to change practice and advise women against the flu vaccine. On the contrary, I continue to advocate and support flu vaccines for women, especially pregnant women. The flu is a devastating illness that can lead to serious, or severe, illness and even death. Less than a century ago women, and children, died of the flu in large numbers and the virus could sweep through communities or neighborhoods rapidly; it still can. The flu vaccine minimizes the chances of contracting the flu, or lessens the impact of a flu infection if it occurs. The American College of Obstetrics and Gynecology (ACOG), the Centers for Disease Control and Prevention (CDC), and other key professional medical and nursing women’s health organizations, continue to promote, support and advocate for women receiving the flu vaccine, especially in pregnancy.
What You Can Do
Each pregnant woman is unique, however, so speak with your health care practitioner about your individual risk and whether the flu vaccine is, indeed, right for you.