thats why they invented towels. lol. just dont go in with the thought "i cant get pregnant on my period" if youre not using birth control already. thats a big mistake. as far as messiness goes. you know how heavy you are at whatever times. and as long as you dont get too creative with it, just put a towel underneath you guys and it should be okay. but if youre not comfortable with it, dont do it. but theres only one way to know if youll be okay with it or not.