Melody when I was in 2nd trimester I didn't feel as hungry at all and just ate 3 meals a day. I had a tea break but I wouldn't eat anything.... so I really feel like some of the others have said that its what your body tells you..... if you have large meals your body will feel overfull afterwards, so maybe try taking a break while eating the meal for 5 minutes or so and drink a glass of water to try and not fill up as quickly so you can stop before you become overfull...HTH