Are painful periods a side effect of the Covid vaccines? Demands for more investigations into links after nearly 35,000 women in Britain report irregular menstrual cycles or period pain after getting a jab

Nearly 35,000 British women have come forward to say their periods were disrupted after getting a Covid vaccine, it was revealed today.

The issues — which include an irregular menstrual cycle and painful periods — were reported in the UK up to September 2.

Most affected women found their menstruation returned to normal after one cycle. Issues were linked to Pfizer, AstraZeneca or Moderna vaccines.

No fertility issues were uncovered, according to an analysis of the data by Dr Victoria Male, a lecturer in reproductive immunology at Imperial College London.

Writing in the British Medical Journal (BMJ), she argued more research was needed to investigate the links.

The Medicines and Healthcare products Regulatory Agency (MHRA), the UK’s drug watchdog, has yet to accept any link between Covid jabs and menstrual issues. 

It says: ‘The rigorous evaluation completed to date does not support a link between changes to menstrual periods and related symptoms and Covid vaccines.’

Dr Male suggested the body’s immune response to jabs may trigger a change in the menstrual cycle.

She pointed to previous studies suggesting the HPV vaccine had disrupted women’s menstrual cycles shortly after it was administered. 

But other experts have previously dismissed the theory, saying menstrual problems after jabs were not happening at a higher rate than usual. 

Data on the number of period problems following vaccination was collected from the MHRA’s Yellow Card Scheme, which keeps a record of every case of a potential side effect. 

But this data is reliant on women coming forward, meaning nearly 35,000 figure could be the tip of the iceberg, 

Nearly 35,000 women have now come forward to say their periods were disrupted after getting a Covid vaccine, it was revealed today. (stock) 

Dr Male wrote: ‘Primary care clinicians and those working in reproductive health are increasingly approached by people who have experienced these events shortly after vaccination.

‘More than 30,000 reports of these events had been made to MHRA’s yellow card surveillance scheme.

‘Most people who report a change to their period after vaccination find it returns to normal the following cycle.

‘And, importantly, there is no evidence Covid vaccination adversely affects fertility. In clinical trials, unintended pregnancies occurred at similar rates in vaccinated and unvaccinated groups.’

But she added: ‘Failing to thoroughly investigate reports of menstrual changes after vaccination is likely to fuel these fears.

‘If a link between vaccination and menstrual changes is confirmed, this information will allow people to plan for potentially altered cycles.

Anthropologist says her period came early following Moderna’s Covid jab 

Anthropologist Dr Kate Clancy, from the US, is one of many women who say they have experienced period problems after getting the Covid vaccine. She said after getting her first dose of Moderna her period came a day early, and was stronger than normal

Dr Kate Clancy, a medical anthropologist in Illinois, is one of many women to say they have experienced period problems after getting the Covid vaccine.

She said in February that after getting her first dose of the Moderna vaccine, her period came about a day early.

‘I’m on day three of my period and I am still swapping out extra long overnight pads a few times a day,’ she wrote on Twitter.

‘Typical for me at this time is maybe one or two regular pads (though extra absorbent, Always Infinity ones) for the whole day.’ 

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‘Clear and trusted information is particularly important for those who rely on being able to predict their menstrual cycles to either achieve or avoid pregnancy.’ 

The MHRA says online it is investigating reports that the jabs have triggered period problems and unexpected vaginal bleeding.

But it adds: ‘The menstrual changes reported are mostly transient in nature.  

‘While uncomfortable or distressing, period problems are extremely common and stressful life events that can disrupt menstrual periods.

‘Changes to the menstrual cycle have also been reported following infection with Covid and in people affected by long Covid.’

The MHRA insists: ‘There is no evidence to suggest that Covid vaccines will affect fertility and your ability to have children.’

Guidance published by the Association of Reproductive and Clinical Scientists and the British Fertility Society says there is ‘absolutely no evidence, and no theoretical reason, that any of the vaccines can affect the fertility of women or men’.

The MHRA has yet to uncover any pattern between the vaccines and any increased risk of miscarriage or stillbirth. 

‘Pregnant women have reported similar suspected reactions to the vaccines as people who are not pregnant,’ it says.  

Up to a quarter of women of childbearing age experience menstrual irregularities, which can include heavier or lighter than usual bleeding, delayed or early periods and cramps.

They are often triggered by hormonal changes and stress, as well as certain medical conditions and medications.

Similar issues after vaccination have been reported in the US, but scientists say it is too early to confirm a link.

One in 10 people experience mild side effects from the jab.

Britons are currently warned that they may experience headaches, nausea, achy muscles and pain at the injection site after getting their jab.

The NHS also warns of a small risk of blood clots linked to AstraZeneca’s jab.

Babies could be given Pfizer’s Covid vaccine in the US this winter

Pfizer’s Covid vaccine could be rolled out to babies as young as six months in the US this winter, under plans being drawn up by the pharmaceutical giant.

In a move likely to cause international controversy, the company intends to apply for authorisation to immunise American infants within the next two months.

The timeline will depend on the findings of in-house trials looking into whether the vaccines are safe and effective in youngsters aged six months to five years.

Frank D’Amelio, chief financial officer at Pfizer, told an industry conference yesterday that the firm plans to ‘go file’ by November, the Financial Times reports.

‘We would expect to have… data for children between the ages of six months and five years old that we would file with the FDA,’ D’Amelio said at the Morgan Stanley Global Healthcare Conference. ‘I’ll call it in the weeks shortly thereafter the filing of the data for the five- to 11-year-olds.’

Pfizer was already planning to seek approval from the Food and Drug Administration (FDA) for the jabs to be given in children aged five to 11 by October.

But the latest comments confirm the firm’s intention to work its way down much younger age groups. They will be given a lower dose than adults.

Pfizer’s jab, made alongside German partner BioNTech, is already approved for over-12s in Britain.

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Dr Raj Mathur, a consultant in reproductive medicine and the chair of the British Fertility Society, told MailOnline: ‘It does appear that the Covid vaccine can be followed by a transient [lasting for a short time] disturbance in the menstrual cycle in some women.

‘However, the evidence also shows that there is no effect on fertility or on the risk of miscarriage.

‘Women (and men) who have the Covid vaccine demonstrate no change in their sperm quality or chance of success with IVF.’

He added: ‘It is plausible that the vaccine can be associated with some menstrual changes.

‘Firstly, this is a common symptom that women report with any stress or illness.

‘Also, the ovaries contain immune cells and these may be affected in the same way as other parts of the body in response to the vaccine.

‘In summary, yes this effect is possible, but it does not indicate an underlying problem.’

Dr Gemma Sharp, a senior clinical lecturer in molecular epidemiology at Bristol University said it was ‘plausible’ that vaccines could affect the menstrual cycle.

She told the Science Media Centre: ‘It is biologically plausible that vaccines can affect menstrual cycles through short term disruptions to the immune system, but there is no reason to suspect these changes would be persistent or have any lasting effect on fertility.

‘Short-lived changes to the menstrual cycle are part of the body’s normal response to things like stress and immune disruptions.

‘There is no reason to suspect these changes would indicate any long term effects on health or fertility.’

Dr Jo Mountfield, vice president of the Royal College of Obstetricians and Gynaecologists, said: ‘We understand that any changes to periods following a Covid vaccine can be concerning.

‘We want to reassure women that any changes generally revert back to normal after one or two cycles.

‘We would encourage anyone who experiences heavy bleeding that is unusual for them, especially after the menopause, to speak to a healthcare professional.

‘There is no evidence to suggest that these temporary changes will have any impact on a person’s future fertility or their ability to have children.

‘It is important to get vaccinated as the best protection against coronavirus. This is especially important if you are planning a pregnancy, as we know unvaccinated pregnant women are more at risk of becoming seriously ill from Covid.

‘We support calls for more research to understand why women may be experiencing changes to their menstrual cycle after having the vaccine.’ 

Dr Kate Clancy, a medical anthropologist in Illinois, is one of many women to say they have experienced period problems after getting the Covid vaccine.

She said in February that after getting her first dose of the Moderna vaccine, her period came about a day early.

‘I’m on day three of my period and I am still swapping out extra long overnight pads a few times a day,’ she wrote on Twitter.

‘Typical for me at this time is maybe one or two regular pads (though extra absorbent, Always Infinity ones) for the whole day.’