Well, i wouldn't go through them

I'd probably go under. If you go within 1 1/4" of the top/bottom of the joists, you'll need protector plates but seeing as how you have a floor above, that will be hard to do. If you go under, it's less likely anyone will be putting screws or nails etc, though the ceiling except to hang the drywall back. Put the plates where your holes through the studs are. if the drain forces you close to where the ceiling will be, you could run protective conduit or some other means to protect the wire.