The secret is small meals, you'll eat then an hour or so later feel hungry again. A lot of women here who have had children tell me to eat 5 or 6 small meals and to eat light, no sweets etc, salads and such, nothing heavy and water. Also things like nutrigrain bars and such.
Eating 3 big meals like you use to will only leave you feeling heavy and bloated and won't ease the hunger.
It does help, I've noticed a difference in my hunger pattern since taken onboard what they told me.
Also keep in mind that a pregnant woman can gain anything from 12 kilos to 28 kilos, so I'm taking the salad and chicken route ha lol