As someone who was trying to conceive while the vaccine rolled out, this isn’t surprising. People were regularly reporting basal temperature spikes, delayed ovulation, and delayed periods. This is a community that is extremely data-oriented, since with the right measurements you’re able to predict your fertile (or non-fertile) window. I was disappointed to see how little research there was into menstruation at the ti…
From a throwaway because of the potential backlash...This paper is pure bull. They did a survey of 30k people and asked them about their experience and then said that the vaccine didn't cause anything and that we should trust our institutions. They didn't even have a control (unvaccinated) group! Just 30k vaccinated folks who responded to a survey about whether they perceived more/less bleeding, and such. I'm actuall…
It seems so many commenters here miss that sentence, and live in a mental world where viruses are mostly benign but healthcare is mostly deadly.
Therefore, a statistical control group for such a trial as you describe doing is not an unvaccinated cohort for the same time period, but rather for infinite time. Thus your results will require substantial adjustment for the eventual rates of encountering COVID (and the estimated rates of equivalent adverse effects), since your trial will presumably be of finite duration.