Can COVID-19 vaccination cause changes in menstrual bleeding?

Vaccine studies rarely consider menstruation as a variable, focusing on how vaccines affect fertility and pregnant women. Studies from the US Vaccine Adverse Event Reporting System (VAERS) have shown that vaccines and immune responses can affect menstruation, indicating the need for further research.

Recent research Science Advances We investigated changes in menstrual bleeding after vaccination against the severe acute respiratory disease coronavirus 2 (SARS-CoV-2) in premenopausal and postmenopausal women of different genders. Results showed heavier menstrual bleeding episodes in women who generally had regular menstruation and breakthrough bleeding among postmenopausal women, and in women with sex-verifying hormones and long-acting contraceptives. rice field. These changes were associated with age, ethnicity, pregnancy or birth history, and side effects of the Coronavirus Disease 2019 (COVID-19) vaccine.

Background

Menstruation is the monthly shedding of the endometrium. Earlier reports described unexpected menstrual bleeding after COVID-19 vaccination in 2021. However, there is no standard protocol for monitoring vaccine-related adverse events beyond 7 days. Moreover, the follow-up response does not address the menstrual cycle or bleeding. Therefore, vaccine manufacturers could not explain these menstrual-related changes as accidental events or side effects to vaccination.

Vaccines protect the body from illness by activating the immune system. It involves a cascade of various local or systemic inflammatory responses. The menstrual cycle is an inflammatory and hemorrhagic process. Several studies have investigated the direct effects of vaccination on the menstrual cycle. For example, studies have shown that irregular menstruation is associated with typhoid and hepatitis vaccines. Research in this area is underway due to the acute immunological challenges caused by existing COVID-19 vaccination.

An ongoing survey is being conducted to collect responses from adults during and before menstruation. This preliminary study identified the parameters of the phenomenon of post-vaccination menstrual changes based on the results of the initial analysis. Using the data collected in the first three months, researchers explain the propensity for menstrual bleeding or breakthrough bleeding. The purpose was to answer the following research questions:

• What type of menstrual bleeding changes do women who regularly menstruate after being vaccinated with SARS-CoV-2 experience?
• How often do non-menstrual respondents report breakthrough bleeding after being vaccinated with SARS-CoV-2?
• Can these changes in menstruation correlate with changes in the pattern of menstrual bleeding to provide clues about the mechanisms that function in the womb?

the study

The survey consisted of data from the first three months of respondents in a sample (N = 39,129) of women aged 18-80 years. People without menstruation have premenopausal women (using long-acting reversible contraceptives (LARC), continuous hormonal contraceptives, and / or gender-identifying treatments to stop menstruation) and menstruation at age 55. There were two categories of postmenopausal women. t There was menstruation for at least one year before vaccination with COVID-19.

All subjects were fully immunized and were not infected with COVID-19 (neither diagnosed nor suspected). Overall, 21,620 participants were vaccinated against Pfizer. 13,001 in Moderna; AstraZeneca and 751; 3,469 with Johnson & Johnson; 61 and Novavax; 204 with other vaccines; 23 respondents did not report the type of vaccine.

Survey results

It was noted that increased bleeding was the most common vaccination-related change in menstruation. Changes in the menstrual cycle have been reported by women who menstruate frequently. Overall, 42.1% reported heavy or light menstrual flow after vaccination, while 14.3% reported no or light changes in menstrual flow and 43.6% had no change in menstrual flow after vaccination. I reported that.

However, menstruation can be severe in non-white, Hispanic / Latin, elderly, women diagnosed with reproductive disorders, women who have used hormonal contraceptives, women who have been pregnant, and women who have fever or exhaustion after vaccination. The sex has become higher. .. Both pregnancy history and parity were correlated with heavier menstrual flow. Vaccine type, ethnicity, and the use of hormonal contraceptives, on the other hand, had little effect on changes in menstruation after vaccination.

In addition, women with reproductive status such as endometriosis, menorrhagia, uterine fibroids, polycystic ovarian syndrome (PCOS), and uterine adenomyosis are more post-vaccinated than women with no confirmed reproductive disorders. I reported that the flow of menstruation was heavy.

In addition, non-menopausal premenopausal respondents receiving hormone therapy (N = 1,815) are significantly more likely to experience breakthrough bleeding after vaccination than respondents receiving gender-verifying care. it was high.

Participants who were Hispanic / Latin Americans experienced pregnancy but did not give birth and were diagnosed with reproductive status, participants who were taking only LARC, or had a fever after vaccination. Participants had a high predominance of breakthrough bleeding.

Non-Hispanic / Latin participants, on the other hand, had a lower prevalence of breakthrough menstrual bleeding. The rate of breakthrough bleeding was not significantly affected by the type of vaccine administered, the side effects of the vaccine, or the reproductive history.

Notably, changes in menstruation after vaccination did not appear until one week after vaccination. Therefore, these changes could not be recorded in monitored vaccine trials. The findings may have important implications for the study of breakthrough postmenopausal bleeding from dormant ovaries. Changes in menstruation associated with vaccination may also indicate vulnerabilities in hyperproliferative and vascular or hemostatic women.