The Flu Shot Might Disrupt Your Cycle. Why Didn’t Anyone Tell You?

It’s one thing to be told your body is lying to you. It’s another thing to realize that medical experts never even bothered to ask. A new study out of Oregon Health & Science University just confirmed what many women suspected, but were often brushed off for even suggesting: the seasonal flu vaccine may cause temporary disruptions in a woman’s menstrual cycle.

Specifically, researchers found the shot lengthens cycle duration by nearly a day. Sure, it may be small, but any measurable shift matters, especially for women tracking ovulation either in the hopes of getting pregnant one day or for those trying to avoid it. While the effect is reportedly not dangerous and only lasts short-term, one question looms way larger than the data itself… why in the world are we just now studying this?

For decades, while scientific research reaches levels unthinkable to generations of yore, women’s cycles have, for some reason, been treated like background noise in clinical trials. Irrelevant. Inconsequential. Not worth tracking. And yet, the menstrual cycle is a vital sign—a window into a woman’s hormonal health, fertility, immune function, and more. Generations of yore knew this. Yet modern society conveniently ignores it. 

If something nudges our natural rhythm, it means something changed. The answer lies in a medical establishment that has long sidelined women’s health concerns—not maliciously, perhaps, but systematically and habitually as if our bodies are inconvenient variables rather than valid data sets. 

We Don’t Deserve Shrugs, We Deserve To Be Seen and Heard

This flu vaccine study echoes an all-too familiar pattern that millions of women can and should recognize instantly—especially those who lived through the constant dismissals of the COVID-19 vaccine rollout. 

In 2021 and 2022, women around the world reported menstrual cycle disruptions after receiving the jab. Some said their periods got heavier, some said their cycles skipped entirely, and others said they experienced changes in the duration and intensity. These weren’t isolated anecdotes from fringe groups. No, they were widespread enough to buzz around women’s health forums, cycle-tracking apps, and social media.

Yet, time and time again, mainstream health authorities and many physicians captured by ideological groupthink responded with familiar, deflating shrugs. Your cycle changes were just coincidences to them, perhaps blamed on pandemic stress or even chalked up to collective hysteria rather than an individual, valid, lived experience.

Now, even in this newer flu vaccine study, Oregon researchers had to openly admit that menstrual outcomes are rarely tracked in vaccine trials because they are “not considered clinically relevant.” That phrase should infuriate every woman reading this. It simply translates to: Your period doesn’t matter to us. But any woman who has had to tirelessly advocate for herself in a doctor’s office, or who has been told that her pain and symptoms are just “in her head” knows this isn’t new.

We are not fragile. Our bodies aren’t mysteries. Our cycles aren’t irrelevant. They are signals, and when something alters that pattern, it deserves to be acknowledged, studied, and transparently communicated to the masses.

This gaslighting is part of a deeper systemic rot in how modern medicine approaches women’s health by pretending we are no different than our male counterparts. We’re sidelined, minimized, and our experiences may even be outright erased if they don’t neatly fit into the predominantly male-tested, male-centered data that guides most clinical practice.

While I’m not a medical professional, I do have that basic knowledge of the differences between the sexes that I’d assume most medical professionals could admit to, too. Yet they don’t. Even though we see OB/GYNs, even though we experience major differences in our hormonal makeup and its ebb and flow, even though we have literally different reproductive organs, it’s inconvenient for a post-feminist medical industry to “other” us into a different category.

Recall when Ambien, a popular sleep aid, was found to stay in women’s bodies longer than men’s. This led to morning drowsiness, dizziness, and even an increased risk of car accidents the following day. But guess what? It took 20 years after FDA approval for regulators to realize that women’s bodies metabolized Ambien more slowly than men’s bodies did. The blame is on the clinical trial researchers who hadn’t adequately tested for sex-based differences.

Then, there was the Anthrax Vaccine known as BioThrax, which was administered by the U.S. military to troops (including women) during the late 90’s and early 2000s. Again, not enough research was done into the sex-specific side effects and long-term impacts. Unfortunately, there were disproportionately higher rates of autoimmune disorders, chronic fatigue, and fertility issues in female service members.

And as we know all too recently, when the COVID-19 vaccine was pushed on all people, women were found to account for 78% of all adverse event reports submitted to the Vaccine Adverse Event Reporting System (VAERS) for early adopters. Once again, sex differences weren’t prioritized in early trials, and even as time passed, menstrual cycle tracking was not included in Phase III clinical trials.

The Truth Costs You Nothing; A Lie Could Cost You Everything

Here’s what I’m not saying: I’m not telling women not to get vaccinated. I’m not needlessly fear-mongering, nor am I rejecting science. What I am asking for is something way more simple and foundational… just tell us the truth!

Informed consent is more than a legal formality where you haphazardly sign a waiver on a clipboard 10 minutes before your appointment. It’s the ethical backbone of all forms of medical care. It means being provided full, accurate information about both the benefits and risks for any intervention—and that includes risks unique to women’s biology. 

When the medical establishment fails to even study, let alone disclose, how a treatment affects something as important as our menstrual cycle, they’re not just ignoring data deemed “not clinically relevant.” They’re violating the principle of informed consent. This isn’t some “anti-science” mumbo-jumbo; this is self-preservation.

If the last half decade has taught us anything, it’s that medical authorities are not infallible. Women aren’t wrong to demand more data, more nuance, and more transparency before rolling up our sleeves for another jab, year after year. The erosion of trust we’re seeing is the predictable result of being dismissed one too many times, and we all know the saying, “Hell hath no fury like a woman scorned.”

If people really cared about empowering women’s bodies—not just with catchy social media bio slogans and bumper sticker activism—they wouldn’t settle for a one-size-fits-all medicine designed around male physiology. They wouldn’t be silent about the fact that women were excluded from most clinical trials until 1993, and that the legacy of male-centric data still shapes the drugs and interventions prescribed to us daily.

You wouldn’t accept skincare that ignores your personal skin type, or makeup formulated without your beautifully unique undertones in mind. So why are we expected to accept healthcare that ignores the very rhythms of our hormones? The truth is, we’ve been sold empowerment that stops at cosmetics, while genuine bodily autonomy (the kind rooted in informed, sex-specific science) has been quietly neglected. 

If people really cared about empowering women’s bodies—not just with catchy social media bio slogans and bumper sticker activism—they wouldn’t settle for a one-size-fits-all medicine designed around male physiology.

The mainstream medical establishment is still catching up to the idea that women’s cycles aren’t just noise in the data… frankly, they are the data. And every time a pharmaceutical company or regulatory agency does a 180 to studying female-specific outcomes, they’re sending us a clear message: Your body is an afterthought.

That’s not acceptable anymore. We need a Make America Healthy Again era of women’s health, specifically, where consumer empowerment and not blind compliance to “the science” sets the tone. We need real data on how vaccines and pharmaceuticals impact female bodies before those products are rubber-stamped and pushed on us season after season. And we need health authorities to stop treating women’s natural hormonal ebbs and flows as inconvenient distractions from the “real” science. Our biology is the real science, so make no mistake about that.

We are not fragile. Our bodies aren’t mysteries. Our cycles aren’t irrelevant. They are signals, and when something alters that pattern, it deserves to be acknowledged, studied, and transparently communicated to the masses. Women aren’t an afterthought, and you bet that the more the medical establishment acts like we are, the louder we’ll get.