A study has found that adolescent girls who received a COVID-19 booster vaccine experienced shorter menstrual cycles in the four months following the booster, with an average cycle reduction of 5.35 days, especially during the second cycle. This effect was more pronounced when the booster was administered during the follicular phase of the menstrual cycle. However, there were no changes observed in menstrual flow, pain, or other symptoms post-vaccination. The study involved 65 teenage girls, 47 of whom received the booster shot and 18 who did not.
The menstrual cycle length was monitored for three cycles before and four cycles after vaccination in the booster group, and for seven cycles in the control group. Higher baseline stress levels were also linked to shorter menstrual cycles, regardless of vaccination status. The researchers have highlighted the importance of these findings about…
