Can The COVID Vaccines Affect Your Menstrual Cycle?

COVID-19 vaccination is suggested for all females, including those who are pregnant or may become pregnant in the future. It decreases the risk of getting severely ill from the virus and helps protect both mother and child during pregnancy. Though, worries about the vaccine’s possible effects on menstruation have made some cautious to get vaccinated.

Females have testified menstrual deviations after receiving the COVID-19 vaccine both on social media and through official channels for verifying adverse vaccine events. Nevertheless, these reports signify only a small portion of vaccinated women and differ in the menstrual deviations reported.

A squad of investigators led by Dr. Alison Edelman of Oregon Health & Science University looked into whether COVID-19 vaccines cause variations to menstrual cycles. They linked menstrual cycle length that is the time between bleeding and menses which means days of bleeding in vaccinated and unvaccinated females.

Females between ages 18 to 45 data collected by the researchers through a fertility tracking app. Candidates decided to have their data used for research purposes. All the females had normal cycle lengths, from 24-38 days. Information was linked for three menstrual cycles before the first vaccine dose to the three cycles after that. Information was collected for six consecutive cycles among unvaccinated women. Out of the inoculated candidates’ maximum individuals received the Pfizer-BioNTech vaccine, followed by Moderna vaccine and the remaining received Johnson and Johnson vaccine.

The crew found that females who received a COVID-19 vaccine had an average rise in cycle length of nearly one day for each dose. Between women who received a two-dose vaccine, the first dose was linked with a 0.71-day rise in cycle length and the second dose with a 0.91-day rise. Later modification for age, race and ethnicity, BMI, education, and other factors, the alteration in cycle length was still less than one day for each dose.

Getting two vaccine doses within the same menstrual cycle enlarged the cycle length further by about two days on average. Menstrual cycle lengths often swing, and specialists consider cycle variation of up to eight days to be normal. The lengthier menstrual cycles after vaccination reduced in subsequent cycles, signifying they are likely provisional. The investigators did not find any effect of COVID-19 vaccination on the number of menstrual bleeding days.

It is encouraging that the study found only a small, provisional menstrual change in women, says NICHD Director Dr. Diana Bianchi, these outcomes offer, for the first time, a chance to counsel females about what to expect from COVID-19 vaccination thus they can plan consequently.