If you’ve found yourself having a heavier flow, longer delay or worse cramps during your period after getting your COVID-19 vaccination, you’re not alone.

The good news? It’s temporary, at least according to a new study done in America and Norway.

COVID-19 Vaccine Effects on Menstruation

Based on the study conducted by Victoria Male, a lecturer in reproductive immunology, the most common effects experienced were a longer delay in the menstrual cycle and heavier menstrual flow.

In addition to that, there are also other concerns such as more intense cramps that have yet to be researched thoroughly.

COVID-19 Vaccine Effect on Delay in Menstrual Cycle

In the US, 3959 people participated in the study, with 2403 of them being vaccinated. Those who got their first dose of vaccine experienced no delay for their subsequent period, while those who got their second dose experienced an average delay of 0.45 days.

However, this effect was exacerbated for those who received both doses of the COVID-19 vaccine in the same cycle. 358 individuals experienced an average of 2.32 days of delay for their next period.

Additionally, 10.6% of the group experienced a change in cycle length of more than 8 days, which is considered “clinically significant”. For comparison, that value was 4.3% for the unvaccinated cohort.

However, cycle lengths returned to normal by two cycles after vaccination for all groups in the study.

COVID-19 Vaccine Effect on Heavier Menstrual Flow

In Norway, 5688 participants were asked whether they had experienced specific menstrual changes (such as unexpected breakthrough bleeding or worse than normal period pain) in the cycles before and after each vaccine dose.

37.8% of participants reported at least one change from normal, even in pre-vaccination cycles. Subsequently, this figure increased to approximately 39% after the first dose of the vaccine and 41% after the second.

The study identified heavier than normal bleeding as the change most associated with vaccination amongst various other symptoms.

However, just like the first study, it was also shown that the changes are considered minor and are temporary.

Myths Regarding Fertility

Although much of the public concern around this issue arises from misinformation that COVID-19 vaccines cause female infertility, it has been proved to not be the case.

In the clinical trials regarding this topic that were conducted, pregnancy rates were extremely low due to the fact that participants were using contraception and visiting the fertility clinics, and this does not necessarily reflect the broader population of people trying to conceive, Male noted.

On the other hand, contracting COVID-19 may reduce male fertility instead, with studies suggesting that it may reduce sperm count and quality.

This sentiment was echoed by Tomer Singer, medical director at Shady Grove Fertility in New York City.

Singer shared that 5% of the 1,500 patients that he has seen in the past year “reported menstrual changes, but none had their conception potential significantly altered”, and concluded that research should show that the benefits outweigh the risks when it comes to the COVID-19 vaccine and conception.

Singer was not involved in the study.

He also added that the studies “are supporting what [they] as OBGYN’s and fertility specialists in the community have been observing and discussing with [they] patients for two years now”, and that there are also separate studies that have been conducted by other medical professionals as well that have shown similar results.

He ended off by highlighting the importance of consulting a medical professional for individuals who have queries regarding this issue.

“I would encourage every patient who is in the reproductive age of 18-50 who has concerns regarding the theoretical risks of receiving the vaccine to speak to an OBGYN or seek the opinion of a fertility specialist so they can provide them with reassurance and relevant data,” he mentioned.

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The Importance of Awareness

In an email interview with USA TODAY, Male cited how important it is for people to know about the possible changes that the COVID-19 vaccinations can bring about for their periods.

“People need to plan for their periods, so it would be good if we could let them know if they might expect a change one month,” she said.

“People also need to know if vaccination might cause a delay to their period so they don’t start worrying – or celebrating – that they are pregnant if this happens to them.”

The Future of Women’s Health

Male also mentioned in the study that more research and studies need to be done in order to get a better understanding of the vaccines’ effects on women.

This is especially so for the issue of hormonal conception, as it will allow medical professionals to better understand if sex hormones are the cause of these changes in the menstrual cycle.

The need for more extensive research is also due to how vulnerable groups, such as those with pre-existing gynaecological issues, may be affected by the vaccines differently, and future research may help in aiding them with the appropriate medical help and counselling when it comes to the risks of the COVID-19 vaccination.

Male also urged for women’s health to be taken more seriously.

“The work that has been done represents a step in the right direction, but the fact that it has taken us so long to get here reflects the low priority with which menstrual and reproductive health is often treated in medical research. The widespread interest in this topic highlights how pressing a concern this is for the public. It’s time we started listening to them,” Male concluded.

To read more about Male’s study, click here.

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