Applies to a lot in life

"Why?

Because they weren't being asked."

~ B. Hope 

"Were questions about women's menstrual cycles asked during vaccine trials?"  https://www.koat.com/article/can-the-covid-vaccine-affect-your-period-some-woman-say-yes/36546571

Surprised again.

https://www.chicagotribune.com/coronavirus/vaccine/ct-vaccine-side-effects-period-menstruation-20210420-i4fy7a7tnnbchi654z3o64a7my-story.html