SO … during medical testing Viagra showed promise  to help women with menstrual
Dysfunction issues. 

But since it was known to give men erections, big pharma felt it was more important to make money from it than do more research into making the menstrual cycle more bearable for women. 

Cause … MEN 🤣

https://www.huffingtonpost.co.uk/amp/entry/viagra-period-cramps_uk_64e34bdde4b01168be16eb9b/