Maama Lessans et al.
Objective: To investigate the impact of the severe acute respiratory syndrome coronavirus 2 (SARS-CoV-2) mRNA BNT162b2 vaccine on women’s menstrual cycle.
Results: A total of 219 women met the inclusion critieria. Of them, 51 (23.3%) experienced irregular bleeding following the vaccine. Almost 40% (n = 83) of study participants reported any menstrual change following vaccination. Parity was positively associated with irregular bleeding with 26 (50%) of those suffer- ing from irregular bleeding being multiparous compared with only 53 (31.5%) of women with no irregular bleeding (nulliparous 46% vs 60%, multiparous 50% vs 31%, rest 4% vs 8%, P = 0.049). The presence of medical comorbidities was also significantly higher among patients who experienced irregular bleeding (20.0% vs 6.0%, P = 0.003).
Conclusion: Our study shows relatively high rates of irregular bleeding and menstrual changes after receiving the SARS-CoV-2 mRNA BNT162b2 vaccine. Further research is needed to confirm our findings and to better characterize the magnitude of change and any possible long-term implications.