How do i stop getting stitches in my stomach?

its been 2 months since i began jogging, i have no idea why i always get stitches when i jog. i dont eat anything 3 hours before i go jogging, i drink a little bit before i go, i stretch, i warmup for 10 minutes or 15 , by walking. So why am i getting stitches? i dont have a tapped nerve im sure of it, but i have no idea what else i should do to prevent these stitches. I have to walk instead of jog cause my stomach hurts too much. Also i am an intermediate bodybuilder so cardio is super important for me, however i can never jog because of these nasty stitches. Help pls and thanks a bunch :)!