Not shortly after coronavirus vaccinations were made available last year, women throughout the country began posting on social media about what they thought were bizarre side effects: changes in their periods.
According to recent analysis, many of the concerns were legitimate. According to a research of over 20,000 people from around the world, getting vaccinated against covid may alter the time of the menstrual cycle. When compared to individuals who had not been vaccinated, those who had been vaccinated reported a one-day delay in obtaining their periods.
The data for the study came from a popular period-tracking app called Natural Cycles and included users from all around the world, with the majority coming from North America, the United Kingdom, and Europe. The researchers compared menstrual periods among 14,936 vaccinated people and 4,686 unvaccinated participants using “de-identified” data from the app.
Because app users monitored their menstrual cycles each month, the researchers were able to compare three menstrual cycles before and after immunization to four menstrual cycles in the unvaccinated group.
The findings revealed that, on average, vaccinated people had their periods 0.71 days later following the first dose of vaccination. People who had two immunizations within one menstrual cycle, on the other hand, suffered more disturbances. The average increase in cycle duration was four days in this group, and 13% suffered a delay of eight days or more, compared to 5% in the control group.
According to Alison Edelman, an obstetrics and gynecology professor at Oregon Health & Science University who conducted the study, the effects were transient for most patients, lasting only one cycle before reverting to normal. She stated that there was no evidence that the period side effects had any influence on fertility.
Researchers are unsure why vaccinations appear to impact menstruation cycles, but Edelman believes that the immune and reproductive systems are related and that inflammation or a strong immune response might cause monthly irregularity.
Any change in your period may be stressful, causing fears of an unwanted pregnancy or sickness, and individuals have voiced disappointment that public health officials did not warn them about the potential adverse effects or do more study before releasing the vaccinations.
One significant disadvantage of the research is that it only included women who were not on birth control, had regular periods before to vaccination, and were between the ages of 18 and 45.
The research also did not address all of the concerns that respondents had regarding vaccinations and periods, such as how the injections affect trans males and nonbinary folks. Since the vaccinations were introduced, several people have complained on social media about experiencing longer, heavier, and more painful periods after getting vaccinated. This study did not look at period heaviness or other side effects like cramping, but it did demonstrate that getting vaccinated did not appear to induce longer periods on average.
According to Edelman, preliminary data from another study indicate that receiving a coronavirus vaccination may occasionally result in heavier periods. The data, gathered from over 10,000 people, is still being reviewed, but it revealed that getting vaccinated raised the likelihood of experiencing more bleeding significantly.
She did, however, note that her research only included women with regular menstrual cycles who were not taking hormonal contraception, and that individual experiences may vary greatly.
Other studies have revealed that the vaccinations have a range of impacts on menstruation. A survey released last February 2022 gathered period and vaccine information from 160,000 people, including transgender and postmenopausal women, and discovered that hundreds experienced greater bleeding than normal or breakthrough bleeding.