Why have some women experienced changes to their menstrual cycle following COVID-19 vaccination and can this affect fertility?

There is no evidence whatsoever that COVID-19 vaccination could affect fertility. There have been some reports on minor and temporary changes to women’s menstrual cycle following vaccination. More research is being conducted to understand whether there is a causal link and potential mechanisms involved, for example whether vaccination causes an immune response that might temporarily influence the menstrual cycle. In any case, with the currently available evidence there is no reason to link COVID-19 vaccination and fertility issues.


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