I've lost £90 over that, and still, don't think it's the end of the world.
If he's a **** about it, tell him to grow up. Women bleed, that's what we do. If his mother hadn't of done it, then he wouldn't have been born (because she'd have been infertile). Menstruation and that cycle plays an important part in all human life, and if he can't handle that, then he needs a reality check.