How about fruits like bananas or apples? I loved bananas when i was pregnant. It gives you fibre (no constipation!) but i heard some people say no cooling bananas. But it didn't bother me.
Dried fruits contain fibre too. Maybe prunes, apricots, raisins?
Yoghurt is a healthy and good option too. Contains calcium that you need in abundance now.
You can also have a cup of non caffeinated tea too.
Maybe get a variety of healthy snacks so that you wouldn't get bored.