Some studies have suggested minor changes in the menstrual cycle after COVID-19 vaccination, but more detailed analyses of the menstrual cycle are needed to evaluate more specific changes in the menstrual cycle that are not affected by survey-based recall bias.
Materials and Methods
Using a pretest-post-test quasi-experimental evaluation of menstrual cycle parameters before and after COVID-19 vaccination, we conducted an anonymous online survey of two groups of North American women who prospectively monitor their menstrual cycle parameters daily including bleeding patterns, urinary hormone levels using the ClearBlue Fertility Monitor, or cervical mucus observations. The primary outcome measures were cycle length, length of menses, menstrual volume, estimated day of ovulation (EDO), luteal phase length, and signs of ovulation. Perceived (subjective) menstrual cycle changes and stressors were also evaluated in this study as secondary outcome measures.
Results
Of the 279 women who initiated the survey, 76 met the inclusion criteria and provided 588 cycles for analysis (227 pre-vaccine cycles, 145 vaccine cycles, 216 post-vaccine cycles). Although 22% of women subjectively identified changes in their menstrual cycle, there were no significant differences in menstrual cycle parameters (cycle length, length of menses, EOD, and luteal phase length) between the pre-vaccine, vaccine, and post-vaccine cycles.
Conclusions
COVID-19 vaccines were not associated with significant changes in menstrual cycle parameters. Perceived changes by an individual woman must be compared with statistical changes to avoid confirmation bias.
PMID 35723654 35723654 DOI 10.1089/jwh.2022.0097 10.1089/jwh.2022.0097
Cite this article
Bouchard, T. P., Schneider, M., Schmidt, M., Manhart, M., & Fehring, R. J. (2022). Menstrual Cycle Parameters Are Not Significantly Different After COVID-19 Vaccination. Journal of women's health (2002), 31(8), 1097-1102. https://doi.org/10.1089/jwh.2022.0097
Bouchard TP, Schneider M, Schmidt M, Manhart M, Fehring RJ. Menstrual Cycle Parameters Are Not Significantly Different After COVID-19 Vaccination. J Womens Health (Larchmt). 2022;31(8):1097-1102. doi:10.1089/jwh.2022.0097
Bouchard, T. P., et al. "Menstrual Cycle Parameters Are Not Significantly Different After COVID-19 Vaccination." Journal of women's health (2002), vol. 31, no. 8, 2022, pp. 1097-1102.
Shandley LM et al., 2023·Journal of women's health (2002)
There is a growing body of evidence that ovarian cystectomy may negatively impact ovarian reserve. However, it is unclear whether ovarian cyst surgery puts women at risk of future infertility. This study investigates whether surgery for benign ovarian cysts is associated with long-term infertility risk. Women aged 22-45 years (n = 1,537) were invited to participate in an interview about their reproductive histories, including whether they ever had infertility or ovarian cyst surgery. Each woman reporting cyst surgery was randomly matched to a comparison woman, who was assigned an artificial surgery age equal to that of her match. Matching was repeated 1,000 times. Adjusted Cox models were fit to examine time to infertility after surgery for each match. A subset of women was invited to participate in a clinic visit to assess markers of ovarian reserve (anti-Müllerian hormone [AMH], antral follicle count). Approximately 6.1% of women reported cyst surgery. Infertility after surgery was more common for women reporting cyst surgery than those without surgery after adjusting for age, race, body mass index, cancer history, parity before assigned surgery age, history of infertility before surgery age, and endometriosis (median-adjusted hazard ratio 2.41, 95% simulation interval 1.03-6.78). The estimated geometric mean (95% confidence interval [CI]) AMH levels of those who reported a history of ovarian cyst surgery were 1.08 (95% CI: 0.57-2.05) times those of women who reported no history of surgery. Those with a history of ovarian cyst surgery were more likely to report having a history of infertility compared with age-matched women who reported no history of cyst surgery. It is possible that both ovarian surgery to remove cysts and the conditions that lead women to develop cysts requiring surgery may affect subsequent successful conception.
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Fertility AwarenessApp-Based MethodsFertility Awareness MethodsProspective Cohort Study
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