Do girls talk about periods to guys?

like ive heard some girls just mention them around guys. in my (M) opinion, it seems like something personal, and not something to be shared around guys - maybe to other girls tho.

like earlier, an ex and i were talking. like 'talking'. and she mentioned that she was real sick and period cramps has made it worse etc etc. shes never mentioned those around me. and idk if thats normal or what. especially bc she likes me.

its just a behavioural thing ive picked up on, sorry if i sound like a creep - i really dont mean to be. im curious

edit: another story: once i was at a pool and spoke to a girl. we knew each other, but not close. kinda slightly not cared to disliked each other. she said she cant go swimming bc of her period. i was 14. kinda stranged to me.