Menstrual cycle is one of the important aspects of health for women. Changes in the menstrual cycle can be a sign of changes in overall health. Medications and vaccinations can trigger changes in the menstrual cycle. Therefore, the existence of a Covid-19 vaccine is a particular question for women; is it on the menstrual cycle?

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Methodology

Some women in the United States have reported changes in their menstrual cycles after receiving Pfizer, Moderna and J&J Covid-19 vaccines.

While many have complained about the impact of the vaccine on their menstrual cycle, there has only been one recent study completed in this regard. A Professor of Obstetrics and Gynaecology at Oregon Health and Science University has observed 4,000 women in the United States regarding the impact of the Covid-19 vaccine on the menstrual cycle

The research sample was divided into two, women who had been vaccinated and women who had not been vaccinated. The sample solely included women with regular menstrual cycles. Menstrual data observed were cycle lengths and periods for six cycles or periods.

Outcomes

• Administration of the first dose of vaccine was associated with an increase in the length of the menstrual cycle by 0.71 days.
• Receiving the second dose of vaccine was associated with an increase in the length of the menstrual cycle by 0.91 days.
• There was no change in the duration of menstruation.
• In the subgroup of women who received two doses of the vaccine during the same menstrual cycle, they experienced an increase in cycle length by 2 days. But it returned back to normal over time.

This means that there is a slight temporary change in the length of the menstrual cycle after receiving the Covid-19 vaccine.

Conclusion

The International Federation of Gynaecology and Obstetrics classifies variations in menstrual cycle length that are less than eight days to be normal. So it can be said that there was no significant impact on the length of the menstrual cycle after receiving the Covid-19 vaccine.

Challenges

The length of the cycle and the length of periods are only two of the many characteristics of menstruation. Moreover, the menstrual cycle is not just a monthly cycle but is the culmination of a long series of hormonal events. At least 6 months of data is needed to evaluate the presence of anomalies in the menstrual cycle. However, more in-depth and long-term research is needed to really know the impact of the Covid-19 vaccine on the menstrual cycle as a whole. But there have been findings that the Covid-19 vaccine does not cause health or fertility problems.

For now, there is no need to worry that the COVID-19 vaccine will damage your menstrual cycle, because naturally there will be changes but temporary. Have you experienced any changes to your menstrual cycle after the Covid-19 vaccine?