Cohort study, 2024
Does the COVID-19 booster vaccine affect menstrual cycles in adolescent girls?
Yes. Girls who received the booster had shorter cycles on average, with cycles being 5.35 days shorter than before vaccination, especially in the second cycle after vaccination. Higher stress was also linked to shorter cycles.
What they did
A prospective study comparing 47 adolescent girls who received a COVID-19 booster vaccine to 18 who did not, all aged 13-20 in the United States. The vaccinated group was tracked for 3 cycles before and 4 cycles after vaccination. The unvaccinated group was tracked for 7 cycles. Researchers measured cycle length, flow, pain, and menstrual symptoms monthly and assessed stress at baseline.
What they found
Girls in the booster group experienced cycles that were on average 5.35 days shorter after vaccination, particularly in the second cycle. The unvaccinated group showed no changes in cycle length. Higher stress was linked to shorter cycles and more menstrual symptoms, regardless of group. There were no differences in menstrual flow, pain, or symptoms between groups.
What it means for you
The booster vaccine was linked to shorter cycles in adolescent girls. The effect appeared temporary or localized to the second cycle. Higher stress also affected cycle length. This is a small study and researchers note further investigation is needed to understand the mechanism. The sample may not represent all adolescents.
47
Adolescents in booster group
18
Adolescents in unvaccinated control group
5.35
Average days shorter in postbooster cycles
About the study
- Original title
- A Prospective Study of the Relationship of COVID-19 Vaccination to Menstrual Cycle Characteristics in Adolescent Girls
- Authors
- Payne LA, Seidman LC, Granger SW et al.
- Journal
- The Journal of adolescent health : official publication of the Society for Adolescent Medicine
- Year
- 2024
- Study design
- Cohort study
- Participants
- 65
- What was tested
- COVID-19 booster vaccine
- Open access
- Yes
- Read the paper
- doi.org/10.1016/j.jadohealth.2024.06.023
Topics
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