Vaccination and period – is there anything to be afraid of?

Do vaccines affect the menstrual cycle?

There is no evidence to suggest that taking any vaccine may cause disruption of menstrual cycles .

Among other things, HPV and influenza vaccines have been thoroughly analyzed. After their administration, there were cases of people reporting temporary menstrual irregularities. However, there was no evidence that any of these complaints were related to any of the components of the vaccine.

The immune response may vary from person to person, and many factors influence the menstrual cycle (even the most minor cold can disrupt it, not to mention possible stress).

Can the COVID-19 vaccine cause menstrual disorders?

In Poland, we have available mRNA vaccines (BioNTech/Pfizer, Moderna) and vector vaccines (Astra Zeneca and single-dose " raisin" - Johnson & Johnson). You can read about their characteristics and composition here .

Vaccination against COVID-19 is recommended for all people aged 5 years and older to prevent the disease. The vaccination schedule consists of two doses of the mRNA vaccine or one dose of J&J, an additional dose as part of the primary vaccination for people with severe immune disorders, and a booster dose (for all people).

What are the contraindications to vaccination?

The main contraindication is a severe allergic reaction or anaphylactic shock after taking the first dose. The person qualifying you for vaccination should also know about your possible allergies - especially if they concern vaccine ingredients! The doctor may suggest choosing a vector vaccine in the case of an allergy to polyethylene glycol, which is a component of both mRNA vaccines.

Vaccination is postponed in the case of:

• severe infection (diseases such as angina and respiratory tract infections disqualify this),
• exacerbation of an accompanying chronic disease (e.g. asthma).

The final decision to postpone vaccination is made by the doctor.

We also encourage you to read the article: COVID and menstruation .

Vaccination during menstruation – for or against?

For!

Menstruation is not a contraindication to vaccination or a reason to postpone it. Clinical studies conducted on vaccines do not show a link between bleeding and the effect of preparations against coronavirus. So you do not have to wait for it to end to get vaccinated.

Heavy, irregular or missed periods – a side effect of vaccinations?

The Israeli Ministry of Health reported earlier this year that local doctors had reported unexpected spotting and unusual menstrual bleeding in patients after vaccination.

Dr. Kathryn Clancy, an American anthropologist who teaches at the University of Illinois, also touched on the same topic inher online post . She was prompted to write the post by her own experiences – after receiving the vaccine, her period came a day or two earlier, and the bleeding itself was heavier than usual.

A heated discussion ensued in the comments section of her tweet, with complaints including:

• longer menstrual cycles,
• heavier bleeding ,
• bleeding despite taking oral hormonal contraception ,
• unexpected bleeding (also in perimenopausal women and those taking continuous contraception).

The COVID-19 vaccine has been identified as a potential cause of these anomalies (as a common point in all these stories).

Unusual bleeding from the genital tract and any menstrual cycle disturbances can be symptoms of more serious health problems, which is why they always cause some concern, especially if everything previously went according to a set, individual norm. Therefore, wondering whether these problems may be related to vaccinations, it is worth getting to know the mechanism of action of vaccination in a little more detail .

The vaccine is not a virus , but due to the genetic information about a given pathogen contained in it, it triggers a strong immune response – actually imitating the state of infection . It consists of a number of factors:

• Vaccinations provide the body with information about the virus without causing symptoms of infection and at the same time stimulating immune cells to respond.
• Cells of the immune system (white blood cells, immune cells) perform different functions depending on their type, for example: macrophages engulf and destroy microorganisms, leaving behind parts of them called antigens; T lymphocytes recognize the fragments left by macrophages and stimulate the production of antibodies to attack them.

The immune system consequently creates a post-vaccination memory , i.e. teaches the body to recognize the threat and develop a strategy to fight it. People who have had COVID already have antibodies. However, having had the disease is not a contraindication to getting vaccinated - according to the announcement of the Minister of Health, people who have had the disease can be vaccinated, but not earlier than 30 days after obtaining a positive test for coronavirus.

No vaccine studies have shown a direct link between vaccines and abnormal bleeding. The clue to understanding these anomalies may lie in the immune response. Immune cells are not just a component of blood, they also accumulate in the tissues of many organs. The endometrium, or lining of the uterus, is one of them.

Immune cells play an important role in the functioning of the vagina, so a strong reaction can cause peeling and unexpected bleeding. Activation of the immune system – whether through SARS-CoV-2 infection or vaccination – can temporarily disrupt the menstrual cycle and should not be a cause for concern. Both mRNA and vector vaccines can cause unusual bleeding.

The alarm has been raised – further studies will certainly be conducted to finally confirm (or deny) the link between vaccine administration and menstrual disorders.

Many people, especially those planning to have children, are afraid to get vaccinated because of these disturbing reports. However, there is no evidence linking temporary, short-term menstrual disorders and infertility. The vaccine is safe and recommended for people trying to get pregnant. Studies have shown the presence of post-vaccination antibodies in cord blood, which suggests potential protection against COVID-19 in newborns and infants whose parent was vaccinated during pregnancy.

Female patients trying to conceive do not need to take a pregnancy test before vaccination or delay getting pregnant after taking the COVID-19 vaccine.

Stress and your period – pandemic edition

Chronic stress, which has been a permanent part of the agenda for many of us since the appearance of the coronavirus ( cross out as appropriate: illness, loss of a loved one, problems with work, home budget, and so on ), negatively affects the functioning of the entire body - including, of course, the menstrual cycle .

• Stress causes an increase in prolactin levels – its high concentration inhibits the secretion of hormones responsible for the subsequent phases of the menstrual cycle. This can therefore result inovulation disorders / irregular cycles / secondary amenorrhea .
• Chronic stress effectively disrupts the hormonal balance in the body – including communication on the hypothalamus-pituitary-adrenal axis, and from there it is only a short step to irregular bleeding.

Stress may be a response to the aforementioned symptoms of menstrual cycle disturbances (read more about this topic in the article here ). Since their connection with vaccination is not confirmed in any way, it is impossible to rule out this already known correlation. Let's not forget that many people are simply afraid to get vaccinated.

Society has split into two camps, and just watching this clash can be a little nerve-racking, regardless of which side of the “barricade” you’re on. Ultimately, we’re all playing for the same goal – we want to get back to normal. To make that possible, we need to separate the wheat from the chaff, which means focusing on medical recommendations.

So don't hesitate to see a doctor if you feel you need help - whether it's finding answers to your questions (especially if you've noticed any disturbing, unfamiliar symptoms after vaccination) or seeking psychological support.

I. Efrati, Some Vaccinated Israeli Women Report Irregular Menstrual Cycles, Bleeding , "Haaretz", https://www.haaretz.com/israel-news/some-vaccinated-israeli-women-report-irregular-menstrual-cycles-bleeding-1.9550291 [accessed on 13/07/2021].
J. Gołąb, M. Jakóbisiak, M. Lasek, Immunology , Warsaw 2002, p. 259.
AK Lennartsson, IH Jonsdottir, Prolactin in response to acute psychosocial stress in healthy men and women , "Psychoneuroendocrinology" 2011, vol. 36, i. 10, p. 1530-1539.
V. Male, Menstrual changes after covid-19 vaccination , "The BMJ" 2021, vol. 374, https://www.bmj.com/content/374/bmj.n2211 [accessed on 10/01/2022].
K. McCann, COVID-19: More than 13,000 women report changes to periods after having vaccine but experts say fertility not affected , "Sky News", https://news.sky.com/story/covid-19-more-than-13-000-women-report-changes-to-periods-after-having-vaccine-but-experts-say-fertility-not-affected-12350899 [access from 14/07/2021].
S. Reynolds, Lasting immunity found after recovery from COVID-19 , "National Institutes of Health", https://www.nih.gov/news-events/nih-research-matters/lasting-immunity-found-after-recovery-covid-19 [accessed on 13/07/2021].
L. Sung Ki, K. Chul Jung, K. Dong-Jae, K. Jee-hyun, Immune Cells in the Female Reproductive Tract , "Immune Network" 2015, vol. 15, p. 16-26.
Supporting Mental Health During the COVID-19 Pandemic , "National Institute of Mental Health", nimh.nih.gov/news/science-news/2020/supporting-mental-health-during-the-covid-19-pandemic.shtm [accessed on 13/07/2021].
S. Suzuki, A. Hosono, No association between HPV vaccine and reported post-vaccination symptoms in Japanese young women: Results of the Nagoya study , "Papillomavirus Research" 2018, vol. 5, p. 96-103.
Understanding How COVID-19 Vaccines Work, "Centers for Disease Control and Prevention", https://www.cdc.gov/coronavirus/2019-ncov/vaccines/different-vaccines/how-they-work.html [accessed on 14/07/2021].
COVID-19 Vaccination Guidelines. Interim recommendations of the Centers for Disease Control and Prevention (as of November 29, 2021) , translated by M. Ściubisz, J. Mrukowicz, "Medycyna Praktyczna", https://www.mp.pl/szczepienia/artykuly/wytyczne/266040,stosowanie-szczepionek-przeciwko-covid-19-tymczasowe-zalecenia-centers-for-disease-control-and-prevention-stan-na-25-sierpnia-2021-r [accessed January 10, 2022].