Painful or difficult menstruation is known as

Dysmenorrhea

Explanation:

Dysmenorrhea is the medical term it is like the difficult or painful menstuation or *period.  There are two types of dysmenorrhea; primary and secondary. Primary dysmenorrhea is the most common kind of dysmenorrhea. :)

of

explanation:

answer:

it could come from a variety of sources.

explanation:

..although it was most likely developed through zoonotic transmission, where an infectious disease which usually afflicts when animals jump to humans.