Heavy menstrual bleeding is now considered an adverse effect of Comirnaty (Pfizer/BioNTech) and Spikevax (Moderna) vaccines.
On October 28, 2022, the European Pharmacovigilance Committee (PRAC), of the European Medicines Agency (EMA), established the existence of a causal relationship between the injection of a dose of Comirnaty vaccine ( Pfizer/BioNTech) or Spikevax (Moderna) and the onset of heavier bleeding during subsequent periods.
This announcement was expected by many menstruating people, who have been wondering for more than a year and a half about the impact of vaccination against covid on their cycle.
The data was collected by the French pharmacovigilance system, the analyzes of which were carried out at European level. The report thus notes that cases of heavy menstrual bleeding have been reported after the first, second and booster dose of Comirnaty and Spikevax “. He explains that this unusual bleeding is “ characterized by an increase in volume and/or duration that interferes with the person’s physical, social, emotional and material quality of lifee “.
No impact on reproduction and fertility
The PRAC therefore recommends that “ heavy menstrual bleeding be added to the product information as a side effect of unknown frequency of the COVID-19 Comirnaty and Spikevax mRNA vaccines “. While pointing out that the available data reviewed mainly concerned cases which appeared to be non-serious and temporary in nature » and that he « there is no evidence to suggest that menstrual disorders experienced by some people have an impact on reproduction and fertility “.
Further, the report explains that the available data on the use of COVID-19 mRNA vaccines before and during pregnancy is reassuring: they do not cause pregnancy complications and reduce the risk of hospitalization of pregnant people and their babies.
The PRAC adds that the file is not closed: healthcare professionals and patients concerned are invited to continue to report the occurrence of heavy menstrual bleeding. Before concluding : ” The PRAC will continue to monitor cases of this condition and communicate further if further recommendations are warranted. »
Still, these findings are the first – from drug control agencies – to confirm something that had been assumed since the start of vaccination campaigns among people of childbearing age. Two studies (one American, the other Anglo-American) concluded in 2022 that there was a slight and temporary lengthening of the cycle, with no effect on fertility.
Period and vaccine reports since June 2021
Let’s go back over a year and a half of reports. As of June 2021, menstruating people vaccinated with Comirnaty (Pfizer/BioNTech) and Spikevax (Moderna) doses are concerned and testify to cycle abnormalities with, in particular, longer cycles and periods, more abundant flows as well as, sometimes , exacerbation of pre-existing symptoms — such as PMS and pain caused by endometriosis.
At that time, it was only diffuse testimonies, often on social networks, and whose scientificity was insufficient to draw any conclusion. But the people affected by these disorders, which they attribute to the vaccine, generally come up against doctors who are at best deaf to their concerns, at worst contemptuous.
At the end of July 2021, after people who had encountered disorders in their cycle had made reports, the ANSM noted that the disorders of the menstrual cycle observed after vaccination against covid constitute a potential signal. However, she advises, a week later, that it is not possible to establish a causal link.
The deafening silence fed antivax theses
It is a deafening silence on the subject that accompanies the end of the year 2021 with always menstruating people who wonder about cycle anomalies and who come up against a wall. A silence which, moreover, feeds the conspiratorial theses and which feeds the collective ” where is my cycle — whose links with antivax figures and movements no longer need to be demonstrated.
In February 2022, the European Medicines Agency (EMA) took an interest in the subject by launching an assessment of the cause and effect relationships between mRNA vaccines and cycle disorders. In June 2022, the European agency was still carrying out the evaluation.
Boost in the summer, answers in the fall
Perhaps to speed up this development by collecting more data, the ANSM communicated during the summer of 2022 to patients on the procedures for reporting disorders potentially attributable to vaccines against covid. It is also perhaps to meet the expectations of patient associations and healthcare professionals that the ANSM met in July 2022 to discuss the file. It would have been possible for the ANSM to conduct a field survey (for example by telephone to survey menstruating people who received one or more doses of vaccine) but, according to our information, this was not done.
It was therefore on October 28 that the report of the European Pharmacovigilance Committee was published, logically relayed by the ANSM, which encourages health professionals and people affected by post-vaccination cycle disorders to report. She points out that other disorders such as longer cycles, delays or absence of periods, bleeding between periods, and an increase in endometriotic pain have also been reported. This means that eventually they may be added to the list of undesirable effects.
The long time of drug monitoring
Why did these conclusions take so long to arrive? We must first consider the potentially long duration of pharmacovigilance. Mahmoud Zureik is professor of epidemiology and public health at the University of Versailles Saint-Quentin-en-Yvelines and director of the Epi-Phare structure. He explains to us the complementarity of two approaches allowing knowledge of the possible adverse effects of vaccines.
Pharmacovigilance “is based on the passive declarations of health professionals and patients”
The first is pharmacovigilance: “ It is based on the passive declarations of health professionals and patients. There is no control group. Although the plausibility of the adverse effects described can be judged, this type of approach does not make it possible to determine the frequency of occurrence of these effects. In addition, not all reported events that occur following exposure to a drug, for example a vaccine, are necessarily (or obviously) attributable to this vaccine. Finally, there are notorious phenomena of under-declaration. It is thanks to this pharmacovigilance that the cycle disorders that occurred after vaccination against covid were brought to light, and that their extent could finally be considered.
The second approach is based on pharmacoepidemiology: “ It works like a phase 3 clinical trial — without the randomization. The frequency of adverse events in a group of patients who have taken a drug is compared to a group of controls who have not taken the same drug. This is based on the use of a database. In this case, in particular, EPI-PHARE: these are the anonymized data of hospitals and reimbursement of health insurance, containing all the acts, consultations, prescriptions of reimbursed medicines of 67 million people insured in France since 2006.
Thanks to that, ” we can study the associations between taking a drug and the occurrence of possible adverse effects… that is to say, provide arguments on the cause and effect relationship and determine their frequency “, explains the epidemiologist. He adds that the two approaches are, in fact, complementary and necessary. ” Pharmaco-vigilance can be more reactive in certain circumstances. Pharmaco-epidemiology may be slower to draw conclusions but more solid. Moreover, the pharmacoepidemiological approach is more relevant when it comes to the study of late and distant adverse effects in relation to taking the drug (cancer, myocardial infarction, etc.). »
We guess here that pharmaco-epidemiology had its role to play in the monitoring of adverse effects on the cycle. The EPI-PHARE data may have been insufficient: not only did not all the people concerned necessarily consult for these disorders, but it is likely that most did not receive medication and even less that they were hospitalized for this reason. Therefore, the collection and analysis of data from patients and health professionals has been a cornerstone of the conclusions of the monitoring bodies. It is likely that the ANSM and the PRAC waited for the reports to be really massive for the potential signal to turn into proven adverse effects.
Minimized side effects?
Other reasons may be added. Dr. Christian Lehmann, general practitioner, followed the file of vaccination against covid. If he is one of the promoters of vaccination as an essential element in the fight against the pandemic and against the excess mortality it engenders, he remains no less critical.
The question of the rules was “despised”
They explain : “ From the start of the vaccination campaign, possible adverse effects were minimized if not denied. Remember to this visual shared by Olivier Veran in July 2021: showing a look-alike of Pierre Niney riding a pedal boat, this one said: ‘If you have aches after the vaccine, don’t worry, it’s because you’ve pedaled too much’ . Thus, when the adverse effects were considered mild, they became invisible on the pretext of not harming the motivation of the French to be vaccinated.
Christian Lehmann adds: “ To this general desire to minimize is added the fact that menstrual disorders are something common for which it can be difficult to make the link with vaccination – unless you take the subject seriously from the outset.. “And the fact is that longer cycles or heavy periods are” often scornfully regarded as uninteresting women’s business “, deplores the doctor for whom this lack of transparency is a gross error which has fueled distrust of vaccines.
Today, the data we have are reassuring in that the disorders described are transient and benign (which does not mean that they are not anxiety-provoking or have no impact on quality of life). In addition, they are otherwise less serious than a covid condition with the risk of complications – cardiovascular, neurological… and long Covids that it induces.… But which is all the same less reassuring, as explained Christian Lehmann, is that “thehe mechanisms that lead to heavier periods are not yet understood. »