Cohort study, 2023
Does COVID-19 vaccination change the menstrual cycle?
About 25% of vaccinated people reported temporary menstrual changes, most after the second dose. The vaccines are safe and effective, but the study could not determine whether changes were caused by the vaccine or are normal cycle variation.
What they did
Followed 545 vaccinated people who were unpregnant and pre-menopausal. Collected self-reported data on menstrual changes from May to December 2021.
What they found
25% reported menstrual changes. Most changes occurred after the second dose (56%). Common changes were irregular periods (43%), increased premenstrual symptoms (34%), increased menstrual pain (30%), and heavy or prolonged bleeding (31%). High stress and higher BMI were linked to greater odds of changes. Prior COVID-19 infection was linked to lower odds.
What it means for you
If you get a COVID-19 vaccine, there is about a 1 in 4 chance of temporary menstrual changes, especially after the second dose. The main limitation is that people reported changes themselves rather than being medically measured, and the study cannot determine whether the vaccine caused the changes or they are normal cycle variation.
25%
reported menstrual changes after vaccination
56%
reported changes after second dose
43%
reported irregular menstruation
About the study
- Original title
- COVID-19 vaccination and changes in the menstrual cycle among vaccinated persons
- Authors
- Farland LV, Khan SM, Shilen A et al.
- Journal
- Fertility and sterility
- Year
- 2023
- Study design
- Cohort study
- Participants
- 545
- What was tested
- COVID-19 vaccination (Pfizer-BioNTech, Moderna, or Johnson & Johnson)
- Open access
- Yes
- Read the paper
- doi.org/10.1016/j.fertnstert.2022.12.023
Topics
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