Every single question you have about COVID vaccines and your period, answered.

COVID has drummed up over 5.9 trillion search queries in Google since it arrived in our lives a year ago. And for good reason: it's a rather confusing disease that has triggered a pandemic and a global dash to generate a vaccine.

While we've hit the milestone of developing not one, but multiple vaccinations fit for the job of staving off COVID-19 symptoms and lessening the spread of the virus - there are some questions around the symptoms we should expect after getting jabbed.

And we have specific questions around COVID vaccines and... periods. 

Watch: There are girls all over the world who miss school due to their periods. Post continues after video.

Video via CARE Australia.

Why? Well, there have been murmurings of late periods, breakthrough bleeding and periods coming back for people who have already gone through menopause.

So, before we all got ahead of ourselves, we checked in with the experts to get the scientific response to your burning COVID-period questions. 

Here's what they had to say. 

Can the COVID vaccine mess up my cycle?

In short, it potentially can. But if it does, it's more of a nuisance than a concern.


According to Dr Imaan Joshi, "Based on current evidence, there does not seem to be an increased risk of menstrual issues and any that may occur are temporary and mild after any of the vaccines."

The evidence referred to is a small amount of overseas studies and anecdotal evidence, as there hasn't been a whole lot of research into the COVID vaccine's impact on cycles yet. 

"Expert guidance at the moment is still that the risk of a heavier than normal period should not deter women from getting vaccination, as any issues are usually temporary and mild with no effect on fertility," Dr Joshi added. 

In terms of overseas data that we have (as there are not enough vaccinated individuals in Australia yet to draw data from), there was an article published this month in the UK. Within it, almost 4000 British women reported period irregularities after a COVID vaccine - and that included Pfizer, Astra Zeneca and Moderna patients in the mix. 

Beyond these findings, Dr Kieran Kennedy shares that there has been "anecdotal (report based) information arising about women noticing changes to their period after receiving a COVID vaccination".

However, Dr Kennedy is keen to assure you that "at the moment this far and away appears to be an exception rather than the rule, with most women who’ve been vaccinated reporting no changes or impacts on their menstrual cycle at all". 

"In those who have reported changes, it appears that missed, more painful, longer or heavier periods than usual have occurred. In the vast majority it looks like this has been temporary (single cycle) and then things return fully to normal."


Does the COVID vaccine impact fertility?

There is no evidence (amongst the small studies conducted so far) to suggest the COVID vaccine has any negative effect on your fertility.

Here's what Dr Kennedy has found on the topic of COVID vaccines impacting fertility:

"What’s really important to point out here is that reports that COVID vaccines might harm or disrupt hormone cycles, fertility, miscarriage rates or pregnancy aren’t backed. A lot of super anxiety-provoking myths were floating around the internet when the vaccines first launched and one of these was that receiving the vaccine might impact a woman’s fertility. Fairly extensive research and evidence now exists to show this is absolutely not the case - even if women notice a temporary change to their period after receiving a vaccine, there’s no apparent link to any harm on fertility."


Which COVID vaccine causes the most irregular periods?

From the same report mentioned about, the data (collated until May 17 by the Medicine and Healthcare products Regulatory Agency) reported the following stats from the 4000 women who recorded menstruation irregularities:

- 2734 irregular periods related to AstraZeneca

- 1158 irregular periods related to Pfizer

- 66 irregular periods related to linked to Moderna

When we're discussing 'irregular periods', this can mean anything from a period being a little heavier than usual, to delays in the cycle and unexpected spotting. 

And while a correlation between the COVID vaccines and irregular periods has been made in this data, Dr Joshi is keen to flag that, "the number of reports of menstrual disorders and vaginal bleeding is low in relation to both the number of females who had received COVID-19 vaccinations and how common menstrual disorders are generally.”

In other words, this is the usual amount of 'period deviations' found in any medical research. And there's potential that people are attributing irregularities in their period to the COVID vaccine they received, even though they may have had these irregularities without it. 


It's important to note that as it stands, medical advice currently does not list menstrual irregularities as a side effect to 'watch for' as it's not deemed a danger.


Are COVID vaccines bringing back periods for perimenopausal or postmenopausal women?

According to Dr Joshi, "the commonest age period irregularities have been reported is the 30-49 bracket, so technically perimenopausal and postmenopausal women may be included in that group, though there are no studies specifically looking at post-menopausal who had a bleed post-vaccine."


That being said, there has been some new research (again, published internationally because there are not enough stats in Australia) out of the UK that cited a small number of "postmenopausal women and trans men who normally do not bleed due to being on hormones, reported unexpected bleeding after the covid-19 vaccine".

Dr Kennedy agrees here, saying: "Alongside reports of some women noting changes to their usual period, there are also a smaller number of reports of peri or post-menopausal women noting spotting or light bleeding after their vaccine. Research and further data collection is ongoing at the moment, but it doesn’t appear that this is occurring due to a harmful impact on the uterus or the reproductive cycle."

So should perimenopausal or postmenopausal women who experience bleeding outside of their periods go to the doctor ASAP? In short, yes - but just to check for factors beyond a COVID vaccine reaction.

"Any new or re-emerging bleeding or period after a woman has reached menopause should signal a need for a checkup with your doctor as there are other potential causes that need to be checked out and might because for concern," says Dr Kennedy. "If in doubt, always reach out to your doctor and book a checkup."

As a gynecological insight, we spoke to Dr Nicole Stamatopoulos who was happy to report: "I have not had any women see me at this stage with worsening perimenopausal bleeding or postmenopausal bleeding [following a COVID vaccine]."


While you're here, have a listen to this episode of No Filter, which very nearly didn't make it to air due to extreme anti-vaxxers trolling both Mia Freedman and Mamamia itself. Post continues after podcast.

Why are people randomly bleeding mid-cycle after getting the COVID vaccine?

While it's not a guaranteed response to getting any of the COVID-19 vaccinations, we want to know why bleeding, spotting or an extra visit from Aunt Flo may be occurring. 

"At the moment the answer to this question is still being elucidated too, but there are theories and possible reasons why receiving a vaccine (including those for HPV or the flu for example) might cause a temporary impact on a woman’s cycle," says Dr Kennedy. "This isn’t something that’s been noted strictly to the COVID vaccine alone either - which should offer some comfort! Reports of vaccination for the flu or HPV impacting women’s periods temporarily have been around for many years."

So this is a common bodily reaction to any vaccine, not just a COVID jab.

...But why does bleeding sometimes occur after getting a vaccine?

Dr Kennedy explains that it's a natural immunity response. "The uterine lining consists of immune tissue as does most other areas of the body, and it’s been posited by experts that the body’s normal immune response to create antibodies and let them do their thing after a vaccine, potentially leading to impacts to the uterine lining."


Dr Joshi has found research that echoes this theory. "An immunologist surmises that there are numerous immune cells throughout the body, especially the uterus where they work to regular how and when we bleed for each cycle.

"Her hypothesis is that the vaccine may temporarily impact these immune cells, causing spotting and period irregularities. Likewise, inflammation in the body (due to illness or an immune response) may also temporarily disrupt the timing of ovulation and bleeds - but there is no evidence that any of these changes are permanent or anything to worry about." 

And that's the key bit of information to hold on to: While random bleeding may occur, it will go back to normal and there will be no impact on your overall fertility.



At what point should women go to the doctor if they're experiencing irregularities with their periods?

Even outside of COVID vaccine chats, irregularities in your period should be noted down and discussed with your doctor. Ideally, you'll track your period in some capacity (whether that's in an app or just in a diary) and so you know straight away when something is off kilter.

When you have this information, your doctor can "work with you to determine if you should watch and wait, or if further investigations are needed," Dr Joshi explains.

If you are ever in any doubt, Dr Kennedy always urges anyone concerned to touch base with their GP. 

"If you’re asking yourself the question, then I always like to advise people that’s the point to reach out and book in with your doctor. When it comes to our health, including periods, any significant change from normal, new signs and symptoms or something that lasts far longer than it should, go for a check-up. It’s important that women know that while it looks like some mild temporary changes to their period could occur after a COVID vaccine, there are also many other reasons why a period might become irregular or change. Getting things checked out, and (of course) taking a pregnancy test if a period is missed, are key if notable changes or irregularities occur."


What else do we need to know about the COVID-19 vaccines and periods?

As far as Dr Joshi's concerned, "there is a lot of fear in the community at the moment about the vaccines," and that needs to be addressed. 

"People are fearful and afraid which is fair enough, but equally there is a lot of lack of health literacy as people are getting their information from people who aren't medically trained, or from Google, or friends and family who 'know someone' or who know 'a doctor or nurse who said to wait and see'," she said. 


"During all the trials that led to the approval of these vaccines for use in the wider public, menstrual irregularities were not a feature, and now that more women are reporting them, they are invited to advise NSW Health when asked for feedback if it occurs to you.

"What is important to note is what all doctors and women know menstrual irregularities are common, even for women who are normally like clockwork (especially when stressed, and under pressure). Given the degree of stress the COVID vaccines have caused, it is not unusual to see menstrual irregularities. But even when it would seem they may be linked to the vaccines, these things can anecdotally happen and are usually temporary and usually mild, and certainly not a reason to avoid the vaccine."

...You hear that folks? Not a reason to avoid the vaccine.

Dr Kennedy reminds us: "It is important that myths and misinformation are called out when it comes to COVID vaccinations, as there are many floating around online. There is NO evidence that the vaccine has any impact or potential harm on a woman’s fertility and so getting this message out there and dispelling that myth is one doctors really want the public to know."

Dr Joshia adds: "At the end of the day, it is completely ok to be worried or fearful. But if you find yourself unable to stop worrying or overthinking it, please make an appointment to see your trusted family doctor instead of going down a rabbit hole on the internet."


We note the irony of saying this... on the internet. But Mamamia, as always, is here to provide information for you to start those conversations with yourself and the experts around you. So go forth, chat and make those important decisions for your future. 

Feature Image: Mamamia.

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