Covid Vaccine and Hormonal Changes

I have just returned to work last week after 3 weeks away, spent with my son and his family, who we had not seen for 3 1/2 years as they live in Japan, and Covid stopped all travel. Since being back, I have noticed that many of my patients, who had been doing well for many years, now complaining of symptoms, many related to hormonal/gynecological issues. This was puzzling. Nothing else had changed, except for Covid. I wondered whether the vaccine had caused these changes, and did some research on this issue. – all of these women had been vaccinated – what if the vaccine was the cause of these symptoms? The evidence shows that the mRNA vaccines do mess with women’s hormones – see the article below. This is the only logical conclusion I can make. I am not anti-vaccine – have had all 3, as have all of my family. However, we must remember that these are not vaccines in the usual sense. If you have Tetanus, Diphtheria, Smallpox (now extinct due to vaccination),Mumps, Measles and Rubella – you will not get the disease. This is not true for the Covid vaccines. They do not provide 100% protection, and over time this declines significantly. Could those of you who feel that the vaccine has had some sort of major negative reaction, please email me. I would like to know if I am correct. Unfortunately, there is strong pressure on doctors not to report any reactions to the Vaccine, as they do not want to give any ammunition to the ant-vaxxers. I would hope the authorities would be honest with the public and not try to hide the true extent of side-effects to the vaccines.


Menstrual changes after covid-19 vaccination

BMJ 2021; 374 doi: (Published 16 September 2021) Cite this as: BMJ 2021;374:n2211 Read our latest coverage of the coronavirus pandemic

  1. Victoria Male, lecturer in reproductive immunology

A link is plausible and should be investigated

Common side effects of covid-19 vaccination listed by the UK’s Medicines and Healthcare Products Regulatory Agency (MHRA) include a sore arm, fever, fatigue, and myalgia.1 Changes to periods and unexpected vaginal bleeding are not listed, but 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 for adverse drug reactions by 2 September 2021, across all covid-19 vaccines currently offered.1

Most people who report a change to their period after vaccination find that it returns to normal the following cycle and, importantly, there is no evidence that covid-19 vaccination adversely affects fertility. In clinical trials, unintended pregnancies occurred at similar rates in vaccinated and unvaccinated groups.2 In assisted reproduction clinics, fertility measures and pregnancy rates are similar in vaccinated and unvaccinated patients.3456

MHRA states that evaluation of yellow card reports does not support a link between changes to menstrual periods and covid-19 vaccines since the number of reports is low relative to both the number of people vaccinated and the prevalence of menstrual disorders generally.7 However, the way in which yellow card data are collected makes firm conclusions difficult. Approaches better equipped to compare rates of menstrual variation in vaccinated versus unvaccinated populations are needed, and the US National Institutes of Health has made $1.67m (£1.2m; €1.4m) available to encourage this important research.8

Menstrual changes have been reported after both mRNA and adenovirus vectored covid-19 vaccines,1 suggesting that, if there is a connection, it is likely to be a result of the immune response to vaccination rather than a specific vaccine component. Vaccination against human papillomavirus (HPV) has also been associated with menstrual changes.9 Indeed, the menstrual cycle can be affected by immune activation in response to various stimuli, including viral infection: in one study of menstruating women, around a quarter of those infected with SARS-CoV-2 experienced menstrual disruption.10

Biologically plausible mechanisms linking immune stimulation with menstrual changes include immunological influences on the hormones driving the menstrual cycle11 or effects mediated by immune cells in the lining of the uterus, which are involved in the cyclical build-up and breakdown of this tissue.12 Research exploring a possible association between covid-19 vaccines and menstrual changes may also help understand the mechanism.

Although reported changes to the menstrual cycle after vaccination are short lived, robust research into this possible adverse reaction remains critical to the overall success of the vaccination programme. Vaccine hesitancy among young women is largely driven by false claims that covid-19 vaccines could harm their chances of future pregnancy.13 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. 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.

We are still awaiting definitive evidence, but in the interim how should clinicians counsel those who have experienced these effects? Initially, they should be encouraged to report any changes to periods or unexpected vaginal bleeding to the MHRA’s yellow card scheme. This will provide more complete data to facilitate research into any link and signal to patients that their concerns about vaccine safety are taken seriously, building trust. In terms of management, the Royal College of Obstetricians and Gynaecologists and the MHRA recommend that anyone reporting a change in periods persisting over several cycles, or new vaginal bleeding after the menopause, should be managed according to the usual clinical guidelines for these conditions.714

One important lesson is that the effects of medical interventions on menstruation should not be an afterthought in future research. Clinical trials provide the ideal setting in which to differentiate between menstrual changes caused by interventions from those that occur anyway, but participants are unlikely to report changes to periods unless specifically asked. Information about menstrual cycles and other vaginal bleeding should be actively solicited in future clinical trials, including trials of covid-19 vaccines.


  • Competing interests: The BMJ has judged that there are no disqualifying financial ties to commercial companies. The author declares the following other interests: research funding from the Wellcome Trust and research charity Borne; payments to act as an external examiner for the University of Cambridge and the University of Leeds; and royalties received for my contribution to Immunology 9th edition (Elsevier). Further details of The BMJ policy on financial interests is here:

COVID-19 NEWS: Study to Investigate Impacts of COVID Vaccines on Menstruation


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Johns Hopkins Medicine’s Department of Gynecology and Obstetrics is one of five institutions selected to study the impacts of COVID-19 vaccines on menstruation. Credit: Graphic created by M.E. Newman, Johns Hopkins Medicine, using public domain images

Johns Hopkins Medicine’s Department of Gynecology and Obstetrics is one of five institutions selected by the National Institutes of Health (NIH) to conduct research to explore the potential impacts of COVID-19 vaccination on menstruation. The five one-year grants, totaling $1.67 million, are funded by NIH’s Eunice Kennedy Shriver National Institute of Child Health and Human Development and the NIH Office of Research on Women’s Health.

The NIH research grants were established after many women reported irregular menstrual periods and other menstrual changes after getting the COVID-19 vaccines.

“There may be several reasons why a woman might experience unscheduled menstrual bleeding, abnormal periods or bleeding that is heavier than usual,” says lead investigator Mostafa Borahay, M.D., Ph.D., associate professor of gynecology and obstetrics at the Johns Hopkins University School of Medicine. “This research will help us better understand if there’s a real link between the COVID-19 vaccines and these menstrual changes, or if it’s something else, such as lifestyle changes or pandemic-related stress.”

Borahay and his team hypothesize that the immune response following vaccination may bring immune cells into the endometrium (uterus). This, say the researchers, may result in the menstrual irregularities that women are reporting.

“If there’s a relationship between the COVID-19 vaccines and the menstrual changes, we need to know how it happens,” says Borahay. “Therefore, we plan to examine the response of the endometrium to the COVID-19 vaccination at the biological level.”

Menstruation, or a period, is part of a woman’s monthly reproductive cycle. Each month, a woman’s uterus prepares for pregnancy and thickens its walls by increasing the levels of two hormones, estrogen and progesterone. But when pregnancy does not occur, the uterus sheds its lining as the blood and mucus making up the menstrual flow that leaves the body through the vagina during the period.

For the study, the researchers will collect data from different sources. “Through a collaboration with Clue, a period and ovulation tracking app, we will gather unidentifiable data from users about their menstrual cycle before and following COVID vaccination,” says Malak El Sabeh, M.D., a postdoctoral fellow working on the project in Borahay’s laboratory.

Borahay is available for interviews.

About Dr Colin Holloway

Gp interested in natural hormone treatment for men and women of all ages

Posted on March 21, 2022, in Uncategorized. Bookmark the permalink. Comments Off on Covid Vaccine and Hormonal Changes.

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