I help a lot of moms deal with the common discomforts of pregnancy, and gas is definitely on that list.
A few suggestions for decreasing gas during pregnancy include:
Avoiding foods that contain sulfur including cauliflower, cabbage, oinions- these foods cause gases to form while being digested and the pressure results in odorous gas and discomfort in the mother. They can also cause heartburn later in 2-3rd trimesters.
Chew your food slowly and completely. When you swallow air from rapid eating pockets of air are trapped and cause disturbance in the form of gas. It will either be released from belching, or flatulence.
Try eating small meals. Eating smaller meals will allow your digestive system the break it needs.
Drink well between each meal.
Try fennel seed after meals. Fennel is helpful in stimulating proper digestion and is a galactagogue as well, meaning it helps to stimulate milk flow in lactating moms.
When I was pregnant I focused on eating leafy green vegetables, nuts (those without skins) cashews, pine nuts, and soaked brazil nuts, I ate a lot of raw fruits and vegetables and found that the fiber just moved through my system very well. I didn't suffer from bad gas.