Can COVID-19 vaccines affect the menstrual cycle (period)?
Recent research studies have shown that people who menstruate may observe no changes in their periods after COVID-19 vaccination or they may observe small and temporary changes, including:
- Longer menstrual periods.
- Shorter time between periods.
- Heavier bleeding than usual.
Despite these temporary changes in menstruation, there is no evidence that COVID-19 vaccines cause fertility problems.
Date last reviewed:
Tuesday, Oct 10, 2023