Is It Normal To Be Gassy Before Period?

I noticed I was more gassy before my period after I stopped using birth control, so I am not sure if that could have something to do with it. But also I use those symptoms as a warning, like my body telling me, hey tomorrow you are going to get your period. I have noticed that the gas and sometimes stomach aches begin a couple of days before my period. I wish I knew more about what causes it. Sometimes it hurts like hell and sometimes it's uncomfortable because there are times when my stomach even grumbles a lot before my period and I know it's not because I am hungry.. I think a lot of things the body does during certain times is just a warning as to what it's going to do next.

Yes I guess so...I too have these problems with having more gas production just before the periods start..and also I feel there is relation to some body heat being more during at that time and hence being more gassy due to incresaed body heat just before you start your periods.  Anyone with any more suggestions??